Failure in mesh creation with Plydrops

[sange000000]

Hi, I have this issue with the Prevabs mesh file generation when I give begin and end ply drops to my lamina. The begin & end for making plydrops generally works without the bbox2 component in this example. But with the bbox2 component and with the plydrop begin and end commands the prevabs mesh file creation gets terminated. It works sometimes by slightly altering the begin & end position, but my mail analysis where I have multiple drops it is difficult to hack every ply drop location. I have attached the file here.
to_Github.zip
Please could you help me solve this issue

[sange000000]

The reason for having a thin wall bbox2 element is that I wish to add an iso fill inside this box. Here in this case the box depth is big, I can increase to a thicker box wall. But, in my original problem the box depth is very narrow (at some points) so I need to have a thin wall boundary for bbox2 having a thickness less than half the box depth at any location.