To answer Jim’s question: the doorhandles were glued with a 2-component epoxy to the doors.
The protruding ends of the handles got a drop of epoxy at the back of the doors as well.
After hardening of the epoxy I shortened the ends with a wire cutter just leaving the drops epoxy intact.
The holes in the rear wall were meant for receiving the ends of the doorhandles so the doors fit smooth to the rear wall.
I guess if you completely file off the protruding ends of the handles the connection is still strong enough but I did it my way.
The hinges were made of Evergreen 0,025 inch/0,64mm plastic rod which were also glued in postion with 2c-epoxy.