Yes, Duong is right. model is not the problem. The bescene.cs do.
Here is my tips, after edit using kit model switcher 10, you will get A NEW bescene.cs file. Use FileM10 and copy that file into zdata file (is it zdata04.big?), but you have to rename the file exactly like FESCENE.CS filename. It looks like a folder name.
I do this by save the filename in NOTEPAD. So everytime I did this, I just edit bescene.cs name using copy-paste.
Try it, and see if you can solve the crash problem.
If it still crash, and you really think my model as the reason, I don't think you will like my new
untuck_right_chest_no_position which I will release next week together with techfit-like bodyfit model. the former model have been edited heavily and uniquely.
NOTE : If you this one, you will have to do it everytime you change the bescene.cs. That is why we prefer delete the file from zdataxx.big and just rely on the folder.