B1 with GDML import - can't change gun location

I modified the basic/B1 example to load a GDML input geometry.
For the interactive method, I am not able to change the gun position to the “Tracker” volume located behind the lens of the example telescope gdml input file.

You can clone my project with
git clone https://github.com/swissco67/B1dose.git

An interactive run will require to provide the gdml input file like

…/B1dose-build$ ./b1dose Sample1.gdml

Also not sure what’s wron to get a crash for the batch mode run?