Slight overlap in the detector structure

Please fill out the following information to help in answering your question, and also see tips for posting code snippets. If you don’t provide this information it will take more time to help with your problem!

Geant4 Version: 10.6.3
Operating System: Linux bat 6.12.22+bpo-amd64
Compiler/Version: g++ (Gentoo 14.2.1_p20240921 p1) 14.2.1 20240921
CMake Version: 3.30.5

I’m really looking forward to getting solutions to these problems.
It always reports errors of minor overlaps when I tried to construct a PMT using gdml file.

Running geometry overlaps check...
Closing geometry...
Finish closing. Using 0.0037563 s.
Checking overlaps for volume SciLog_PV (G4Orb) ... OK! 
Checking overlaps for volume PMT_1 (G4UnionSolid) ... OK! 
Checking overlaps for volume WindowLog_PV (G4GenericPolycone) ... 
-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : GeomVol1002
      issued by : G4PVPlacement::CheckOverlaps()
Overlap with volume already placed !
          Overlap is detected for volume WindowLog_PV:0 (G4GenericPolycone)
          with CirConLog_PV:0 (G4UnionSolid) volume's
          local point (97.5312,-9.12138,17.596), overlapping by at least: 5.52543 um 
NOTE: Reached maximum fixed number -1- of overlaps reports for this volume !
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

Checking overlaps for volume CathodeLog_PV (G4GenericPolycone) ... 
-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : GeomVol1002
      issued by : G4PVPlacement::CheckOverlaps()
Overlap with mother volume !
          Overlap is detected for volume CathodeLog_PV:0 (G4GenericPolycone)
          with its mother volume WindowLog (G4GenericPolycone)
          at mother local point (-2.28158,-32.8109,178.96), overlapping by at least: 2.74792 mm 
NOTE: Reached maximum fixed number -1- of overlaps reports for this volume !
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

Checking overlaps for volume BodyLog_PV (G4UnionSolid) ... OK! 
Checking overlaps for volume CirConLog_PV (G4UnionSolid) ... 
-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : GeomVol1002
      issued by : G4PVPlacement::CheckOverlaps()
Overlap with mother volume !
          Overlap is detected for volume CirConLog_PV:0 (G4UnionSolid)
          with its mother volume _8inPMT (G4UnionSolid)
          at mother local point (-76.2318,-97.1493,200.296), overlapping by at least: 4.74597 cm 
NOTE: Reached maximum fixed number -1- of overlaps reports for this volume !
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

Checking overlaps for volume CirConInnerLog_PV (G4Polycone) ... OK! 
Geometry overlaps check completed !

Here are the relevant scripts.

<solids>
    <opticalsurface name="surfCon" model="glisur" finish="polished" type="dielectric_metal" value="1.0" reflectivity="1.0"/>
    <opticalsurface name="surf12" model="glisur" finish="polished" type="dielectric_metal" value="1.0" reflectivity="0.15"/>

    <polycone name="CirConInner" startphi="0." deltaphi="360." aunit="deg" lunit="mm">
        <zplane rmin="97.7607" rmax="99.7607" z="17.5905"/>
        <zplane rmin="98.0930" rmax="100.0930" z="17.7271"/>
        <zplane rmin="98.3710" rmax="100.3710" z="17.8658"/>
        <zplane rmin="98.6330" rmax="100.6330" z="18.0112"/>
        <zplane rmin="98.8990" rmax="100.8990" z="18.1704"/>
        <zplane rmin="99.1520" rmax="101.1520" z="18.3318"/>
        <zplane rmin="99.4090" rmax="101.4090" z="18.5052"/>
        <zplane rmin="99.6540" rmax="101.6540" z="18.6786"/>
        <zplane rmin="99.9030" rmax="101.9030" z="18.8632"/>
        <zplane rmin="100.1400" rmax="102.1400" z="19.0464"/>
        <zplane rmin="100.3820" rmax="102.3820" z="19.2401"/>
        <zplane rmin="100.6130" rmax="102.6130" z="19.4315"/>
        <zplane rmin="100.8490" rmax="102.8490" z="19.6330"/>
        <zplane rmin="101.0740" rmax="103.0740" z="19.8315"/>
        <zplane rmin="101.3030" rmax="103.3030" z="20.0399"/>
        <zplane rmin="101.5230" rmax="103.5230" z="20.2445"/>
        <zplane rmin="101.7460" rmax="103.7460" z="20.4589"/>
        <zplane rmin="101.9610" rmax="103.9610" z="20.6691"/>
        <zplane rmin="102.1790" rmax="104.1790" z="20.8889"/>
        <zplane rmin="102.3880" rmax="104.3880" z="21.1041"/>
        <zplane rmin="102.6020" rmax="104.6020" z="21.3287"/>
        <zplane rmin="102.8060" rmax="104.8060" z="21.5483"/>
        <zplane rmin="103.0150" rmax="105.0150" z="21.7774"/>
        <zplane rmin="103.2150" rmax="105.2150" z="22.0011"/>
        <zplane rmin="103.4190" rmax="105.4190" z="22.2342"/>
        <zplane rmin="103.8150" rmax="105.8150" z="22.6985"/>
        <zplane rmin="104.2020" rmax="106.2020" z="23.1696"/>
        <zplane rmin="104.5820" rmax="106.5820" z="23.6471"/>
        <zplane rmin="104.9540" rmax="106.9540" z="24.1304"/>
        <zplane rmin="105.3190" rmax="107.3190" z="24.6193"/>
        <zplane rmin="105.6770" rmax="107.6770" z="25.1134"/>
        <zplane rmin="106.0280" rmax="108.0280" z="25.6122"/>
        <zplane rmin="106.3720" rmax="108.3720" z="26.1156"/>
        <zplane rmin="106.7110" rmax="108.7110" z="26.6232"/>
        <zplane rmin="107.0430" rmax="109.0430" z="27.1349"/>
        <zplane rmin="107.3690" rmax="109.3690" z="27.6503"/>
        <zplane rmin="107.6890" rmax="109.6890" z="28.1694"/>
        <zplane rmin="108.0040" rmax="110.0040" z="28.6918"/>
        <zplane rmin="108.3140" rmax="110.3140" z="29.2175"/>
        <zplane rmin="108.6180" rmax="110.6180" z="29.7462"/>
        <zplane rmin="108.9170" rmax="110.9170" z="30.2778"/>
        <zplane rmin="109.2110" rmax="111.2110" z="30.8122"/>
        <zplane rmin="109.5000" rmax="111.5000" z="31.3493"/>
        <zplane rmin="109.7850" rmax="111.7850" z="31.8889"/>
        <zplane rmin="110.0650" rmax="112.0650" z="32.4309"/>
        <zplane rmin="110.3400" rmax="112.3400" z="32.9752"/>
        <zplane rmin="110.6110" rmax="112.6110" z="33.5218"/>
        <zplane rmin="110.8780" rmax="112.8780" z="34.0704"/>
        <zplane rmin="111.1400" rmax="113.1400" z="34.6211"/>
        <zplane rmin="111.3980" rmax="113.3980" z="35.1737"/>
        <zplane rmin="111.6530" rmax="113.6530" z="35.7281"/>
        <zplane rmin="111.9030" rmax="113.9030" z="36.2844"/>
        <zplane rmin="112.1490" rmax="114.1490" z="36.8424"/>
        <zplane rmin="112.3920" rmax="114.3920" z="37.4021"/>
        <zplane rmin="112.6310" rmax="114.6310" z="37.9633"/>
        <zplane rmin="112.8660" rmax="114.8660" z="38.5261"/>
        <zplane rmin="113.0980" rmax="115.0980" z="39.0903"/>
        <zplane rmin="113.3270" rmax="115.3270" z="39.6560"/>
        <zplane rmin="113.5510" rmax="115.5510" z="40.2230"/>
        <zplane rmin="113.7730" rmax="115.7730" z="40.7914"/>
        <zplane rmin="113.9910" rmax="115.9910" z="41.3610"/>
        <zplane rmin="114.2060" rmax="116.2060" z="41.9319"/>
        <zplane rmin="114.4180" rmax="116.4180" z="42.5040"/>
        <zplane rmin="114.6270" rmax="116.6270" z="43.0771"/>
        <zplane rmin="114.8330" rmax="116.8330" z="43.6511"/>
        <zplane rmin="115.0370" rmax="117.0370" z="44.2260"/>
        <zplane rmin="115.2390" rmax="117.2390" z="44.8016"/>
        <zplane rmin="115.5360" rmax="117.5360" z="45.6617"/>
        <zplane rmin="115.8310" rmax="117.8310" z="46.5330"/>
        <zplane rmin="116.1190" rmax="118.1190" z="47.3964"/>
        <zplane rmin="116.4050" rmax="118.4050" z="48.2709"/>
        <zplane rmin="116.6830" rmax="118.6830" z="49.1374"/>
        <zplane rmin="116.9590" rmax="118.9590" z="50.0149"/>
        <zplane rmin="117.2280" rmax="119.2280" z="50.8842"/>
        <zplane rmin="117.4960" rmax="119.4960" z="51.7645"/>
        <zplane rmin="117.7560" rmax="119.7560" z="52.6365"/>
        <zplane rmin="118.0140" rmax="120.0140" z="53.5194"/>
        <zplane rmin="118.2660" rmax="120.2660" z="54.3940"/>
        <zplane rmin="118.5160" rmax="120.5160" z="55.2793"/>
        <zplane rmin="118.7620" rmax="120.7620" z="56.1659"/>
        <zplane rmin="119.0010" rmax="121.0010" z="57.0440"/>
        <zplane rmin="119.2380" rmax="121.2380" z="57.9328"/>
        <zplane rmin="119.4690" rmax="121.4690" z="58.8130"/>
        <zplane rmin="119.6990" rmax="121.6990" z="59.7039"/>
        <zplane rmin="119.9220" rmax="121.9220" z="60.5862"/>
        <zplane rmin="120.1430" rmax="122.1430" z="61.4791"/>
        <zplane rmin="120.3580" rmax="122.3580" z="62.3632"/>
        <zplane rmin="120.5720" rmax="122.5720" z="63.2580"/>
        <zplane rmin="120.7800" rmax="122.7800" z="64.1440"/>
        <zplane rmin="120.9870" rmax="122.9870" z="65.0405"/>
        <zplane rmin="121.1870" rmax="123.1870" z="65.9282"/>
        <zplane rmin="121.4500" rmax="123.4500" z="67.1195"/>
        <zplane rmin="121.7070" rmax="123.7070" z="68.3122"/>
        <zplane rmin="121.9570" rmax="123.9570" z="69.5062"/>
        <zplane rmin="122.2010" rmax="124.2010" z="70.7015"/>
        <zplane rmin="122.4390" rmax="124.4390" z="71.8980"/>
        <zplane rmin="122.6710" rmax="124.6710" z="73.0958"/>
        <zplane rmin="122.8970" rmax="124.8970" z="74.2947"/>
        <zplane rmin="123.1180" rmax="125.1180" z="75.4946"/>
        <zplane rmin="123.3320" rmax="125.3320" z="76.6957"/>
        <zplane rmin="123.5400" rmax="125.5400" z="77.8977"/>
        <zplane rmin="123.7430" rmax="125.7430" z="79.1007"/>
        <zplane rmin="123.9900" rmax="125.9900" z="80.6107"/>
        <zplane rmin="124.2260" rmax="126.2260" z="82.1123"/>
        <zplane rmin="124.4550" rmax="126.4550" z="83.6250"/>
        <zplane rmin="124.6750" rmax="126.6750" z="85.1291"/>
        <zplane rmin="124.8870" rmax="126.8870" z="86.6442"/>
        <zplane rmin="125.0900" rmax="127.0900" z="88.1506"/>
        <zplane rmin="125.3240" rmax="127.3240" z="89.9656"/>
        <zplane rmin="125.5460" rmax="127.5460" z="91.7821"/>
        <zplane rmin="125.7570" rmax="127.7570" z="93.5999"/>
        <zplane rmin="125.9900" rmax="127.9900" z="95.7272"/>
        <zplane rmin="126.2060" rmax="128.2060" z="97.8461"/>
        <zplane rmin="126.3180" rmax="128.3180" z="99.0007"/>
        <zplane rmin="126.4310" rmax="128.4310" z="100.2150"/>
        <zplane rmin="126.5400" rmax="128.5400" z="101.4310"/>
        <zplane rmin="126.6440" rmax="128.6440" z="102.6460"/>
        <zplane rmin="126.7430" rmax="128.7430" z="103.8620"/>
        <zplane rmin="126.8380" rmax="128.8380" z="105.0780"/>
        <zplane rmin="126.9280" rmax="128.9280" z="106.2950"/>
        <zplane rmin="127.0130" rmax="129.0130" z="107.5120"/>
        <zplane rmin="127.0950" rmax="129.0950" z="108.7290"/>
        <zplane rmin="127.1710" rmax="129.1710" z="109.9470"/>
        <zplane rmin="127.2440" rmax="129.2440" z="111.1650"/>
        <zplane rmin="127.3120" rmax="129.3120" z="112.3830"/>
        <zplane rmin="127.3760" rmax="129.3760" z="113.6010"/>
        <zplane rmin="127.4360" rmax="129.4360" z="114.8200"/>
        <zplane rmin="127.4910" rmax="129.4910" z="116.0390"/>
        <zplane rmin="127.5420" rmax="129.5420" z="117.2570"/>
        <zplane rmin="127.5900" rmax="129.5900" z="118.4770"/>
        <zplane rmin="127.6330" rmax="129.6330" z="119.6960"/>
        <zplane rmin="127.6710" rmax="129.6710" z="120.9150"/>
        <zplane rmin="127.7070" rmax="129.7070" z="122.1450"/>
        <zplane rmin="127.7380" rmax="129.7380" z="123.3640"/>
        <zplane rmin="127.7640" rmax="129.7640" z="124.5840"/>
        <zplane rmin="127.7870" rmax="129.7870" z="125.8040"/>
        <zplane rmin="127.8060" rmax="129.8060" z="127.0240"/>
        <zplane rmin="127.8210" rmax="129.8210" z="128.2440"/>
        <zplane rmin="127.8330" rmax="129.8330" z="129.4630"/>
        <zplane rmin="127.840" rmax="129.840" z="130.6830"/>
        <zplane rmin="127.844" rmax="129.844" z="131.9030"/>
        <zplane rmin="127.844" rmax="129.844" z="132.433"/>
    </polycone>
   <polycone name="CirConOuter1" startphi="0." deltaphi="360." aunit="deg" lunit="mm"> 
        <zplane rmin="50.0926" rmax="126.460" z="-143.11635"/>
        <zplane rmin="128.788" rmax="132.788" z="-141.242"/>
        <zplane rmin="130.248" rmax="134.248" z="-135.896"/>
        <zplane rmin="131.222" rmax="135.222" z="-118.367"/>
        <zplane rmin="145.825" rmax="149.825" z="-118.016"/>
        <zplane rmin="145.825" rmax="149.825" z="-98.042"/>
        <zplane rmin="110.778" rmax="114.778" z="-97.714"/>
        <zplane rmin="110.778" rmax="114.778" z="-91.868"/>
        <zplane rmin="108.831" rmax="112.831" z="-85.030"/>
        <zplane rmin="103.477" rmax="107.477" z="-81.569"/>
        <zplane rmin="96.662" rmax="100.662" z="-80.531"/>
        <zplane rmin="99.096" rmax="103.096" z="-74.221"/>
        <zplane rmin="102.503" rmax="106.503" z="-66.945"/>
        <zplane rmin="103.477" rmax="107.477" z="-56.236"/>
        <zplane rmin="103.963" rmax="107.963" z="-29.446"/>
        <zplane rmin="103.963" rmax="107.963" z="-6.061"/>
        <zplane rmin="106.884" rmax="110.884" z="-6.089"/>
        <zplane rmin="107.858" rmax="111.858" z="9.005"/>
        <zplane rmin="111.265" rmax="115.265" z="14.819"/>
        <zplane rmin="117.106" rmax="121.106" z="23.533"/>
        <zplane rmin="122.947" rmax="126.947" z="31.761"/>
        <zplane rmin="128.301" rmax="132.301" z="40.480"/>
        <zplane rmin="132.196" rmax="136.196" z="48.725"/>
        <zplane rmin="133.656" rmax="137.656" z="57.481"/>
        <zplane rmin="133.656" rmax="137.656" z="73.070"/>
        <zplane rmin="133.656" rmax="137.656" z="89.635"/>
        <zplane rmin="133.169" rmax="137.169" z="103.280"/>
        <zplane rmin="136.576" rmax="140.576" z="119.812"/>
        <zplane rmin="129.844" rmax="140.576" z="130.530"/>
        <zplane rmin="129.844" rmax="140.576" z="132.5"/>
    </polycone>

    <subtraction name="CirConOuter">
        <first ref="CirConOuter1"/>
        <second ref="CirConInner"/>
    </subtraction>
    <union name="CirCon">
            <first ref="CirConOuter"/>
            <second ref="CirConInner"/>
    </union>
    
    <genericPolycone name = "window" startphi="0" deltaphi="360" aunit="degree" lunit= "mm">
        <rzpoint     r="101.5" z="133."/>
        <rzpoint     r="100.8692" z="138.7186"/>
        <rzpoint     r="100.1225" z="143.5679"/>
        <rzpoint     r="99.0024" z="147.6711"/>
        <rzpoint     r="97.1356" z="152.8934"/>
        <rzpoint     r="95.2688" z="156.9966"/>
        <rzpoint     r="93.0287" z="161.0998"/>
        <rzpoint     r="90.0418" z="165.9491"/>
        <rzpoint     r="86.3082" z="170.7983"/>
        <rzpoint     r="82.2013" z="175.2746"/>
        <rzpoint     r="79.2145" z="178.2587"/>
        <rzpoint     r="75.8542" z="181.2429"/>
        <rzpoint     r="72.1207" z="184.227"/>
        <rzpoint     r="67.2670" z="187.5842"/>
        <rzpoint     r="62.4134" z="190.5684"/>
        <rzpoint     r="56.8130" z="193.5525"/>
        <rzpoint     r="51.2127" z="196.1637"/>
        <rzpoint     r="44.4922" z="198.7748"/>
        <rzpoint     r="35.9050" z="201.386"/>
        <rzpoint     r="30.3047" z="202.878"/>
        <rzpoint     r="20." z="203"/>
        <rzpoint     r="6.0364" z="206."/>
        <rzpoint     r="0." z="206."/>
    </genericPolycone>
    <polycone name = "thesphere" startphi="0" deltaphi="360" aunit="degree" lunit= "mm">
        <zplane rmin="0" rmax="50.0926" z="-10.1163"/>
        <zplane rmin="47.0926" rmax="50.0926" z="-0.0448"/>
        <zplane rmin="47.0926" rmax="50.0926" z="32.408"/>
        <zplane rmin="47.0926" rmax="50.0926" z="39.1223"/>
        <zplane rmin="47.0926" rmax="50.0926" z="44.3446"/>
        <zplane rmin="47.4659" rmax="50.4659" z="47.3288"/>
        <zplane rmin="48.5860" rmax="51.5860" z="52.551"/>
        <zplane rmin="50.0795" rmax="53.0795" z="56.6543"/>
        <zplane rmin="51.9462" rmax="54.9462" z="60.3845"/>
        <zplane rmin="53.8130" rmax="56.8130" z="63.7416"/>
        <zplane rmin="56.4265" rmax="59.4265" z="67.0988"/>
        <zplane rmin="58.6667" rmax="61.6667" z="69.71"/>
        <zplane rmin="61.2802" rmax="64.2802" z="72.3211"/>
        <zplane rmin="64.2670" rmax="67.2670" z="74.5592"/>
        <zplane rmin="69.1207" rmax="72.1207" z="78.2894"/>
        <zplane rmin="75.4677" rmax="78.4677" z="83.5117"/>
        <zplane rmin="81.8148" rmax="84.8148" z="89.853"/>
        <zplane rmin="85.5484" rmax="88.5484" z="94.3293"/>
        <zplane rmin="88.1619" rmax="91.1619" z="98.0595"/>
        <zplane rmin="90.7754" rmax="93.7754" z="102.5357"/>
        <zplane rmin="93.0155" rmax="96.0155" z="107.0119"/>
        <zplane rmin="94.8823" rmax="97.8823" z="111.1152"/>
        <zplane rmin="96.3757" rmax="99.3757" z="115.9644"/>
        <zplane rmin="97.4958" rmax="100.4958" z="120.4407"/>
        <zplane rmin="98.2425" rmax="101.2425" z="125.2899"/>
        <zplane rmin="98.6159" rmax="101.5" z="133."/>
    </polycone>
    <genericPolycone name = "cathode" startphi="0" deltaphi="360" aunit="degree" lunit= "mm">
        <rzpoint     r="98.5" z="133"/>
        <rzpoint     r="97.869" z="138.7186"/>
        <rzpoint     r="97.122" z="143.5679"/>
        <rzpoint     r="96.002" z="147.6711"/>
        <rzpoint     r="94.135" z="152.8934"/>
        <rzpoint     r="92.268" z="156.9966"/>
        <rzpoint     r="90.028" z="161.0998"/>
        <rzpoint     r="87.041" z="165.9491"/>
        <rzpoint     r="83.308" z="170.7983"/>
        <rzpoint     r="79.201" z="175.2746"/>
        <rzpoint     r="76.214" z="178.2587"/>
        <rzpoint     r="72.854" z="181.2429"/>
        <rzpoint     r="69.120" z="184.227"/>
        <rzpoint     r="64.265" z="187.5842"/>
        <rzpoint     r="59.412" z="190.5684"/>
        <rzpoint     r="53.813" z="193.5525"/>
        <rzpoint     r="48.212" z="196.1637"/>
        <rzpoint     r="41.491" z="198.7748"/>
        <rzpoint     r="32.90" z="201.386"/>
        <rzpoint     r="20." z="202"/>
        <rzpoint     r="0." z="202"/>
    </genericPolycone>
    <polycone name="thepolycone" startphi="0" deltaphi="360" aunit="degree" lunit= "mm">
        <zplane rmin="0" rmax="50.5593" z="-107.0807"/>
        <zplane rmin="52.2263" rmax="55.2263" z="-101.8999"/>
        <zplane rmin="52.4855" rmax="55.4855" z="-58.899"/>
        <zplane rmin="52.4855" rmax="55.4855" z="-56.5676"/>
        <zplane rmin="53.2634" rmax="56.2634" z="-52.423"/>
        <zplane rmin="55.8561" rmax="58.8561" z="-46.7241"/>
        <zplane rmin="58.9674" rmax="61.9674" z="-42.8384"/>
        <zplane rmin="62.3380" rmax="65.3380" z="-40.248"/>
        <zplane rmin="67.7828" rmax="70.7828" z="-37.9166"/>
        <zplane rmin="73.4869" rmax="76.4869" z="-37.1395"/>
        <zplane rmin="76.8575" rmax="79.8575" z="-35.3262"/>
        <zplane rmin="77.8946" rmax="80.8946" z="-32.7358"/>
        <zplane rmin="0" rmax="80.8946" z="-10.1164"/>
    </polycone>
    <union name="Body">
        <first ref="thesphere"/>
        <second ref="thepolycone"/>
    </union>
    <union name="_8PMT">
        <first ref="window"/>
        <second ref="Body"/>
    </union>
    <union name="_8PMTCon">
        <first ref="_8PMT"/>
        <second ref="CirCon"/>
        <position x="0." y="0." z="133." unit="mm"/>
    </union>
</solids>
<structure>
<!-- Cathode -->
    <volume name="CathodeLog">
        <materialref ref="CsPMT"/>
        <solidref ref="cathode"/>
    </volume>
    <volume name="WindowLog">
        <materialref ref="Boro_glass"/>
        <solidref ref="window"/>
        <physvol>
            <volumeref ref="CathodeLog"/>
        </physvol>
    </volume>
    <skinsurface name="skinsrf1" surfaceproperty="surf12" >
        <volumeref ref="CathodeLog"/>
    </skinsurface> 
    <volume name="BodyLog">
        <materialref ref="ABS"/>
        <solidref ref="Body"/>
    </volume>

    <!-- Concentrator -->
    <volume name="CirConInnerLog">
        <materialref ref="AlConcentrator" /> 
        <solidref ref="CirConInner" />
    </volume>
    <skinsurface name="skinsrfc" surfaceproperty="surfCon">
        <volumeref ref="CirConInnerLog"/>
    </skinsurface>
    <volume name="CirConLog">
        <materialref ref="ABS"/>
        <solidref ref="CirCon"/>
        <physvol>
            <volumeref ref="CirConInnerLog" />
        </physvol>
    </volume>

    <!-- ABS主体 -->
    <volume name="_8inPMT">
        <materialref ref="PMTShell"/>
        <solidref ref="_8PMT"/>
        <physvol>
            <volumeref ref="WindowLog"/>
        </physvol>
        <physvol>
            <volumeref ref="BodyLog"/>
        </physvol>
        <physvol>
            <volumeref ref="CirConLog" />
            <position x="0." y="0." z="133." unit="mm"/>
        </physvol>
    </volume>
</structure>
<setup version="1.0" name="Default">
    <world ref="_8inPMT"/>
</setup>

What does this look like? You can start in UI mode even with overlaps, it will just likely crash if you try to run with a primary particle. Overlaps with complicated structures tend to be heavily biased towards uses of the subtract operator.

Thanks very much for your reply. Is there any alternative method instead of using the subtract operator?