Cars cant import mod into ks3 editor

[Roebin]

Hi, ive made a 3d model in blender, but i cant import anything into ks3 editor, because within 10 seconds it crashes without any error message, this is also the case with non modified fbx files.

below is a link to the files ive used, in the folder is the original car, and outside of it are the edited fbx and the donor car. what is the problem exactly? i have not found anything that could help me yet

https://www.mediafire.com/folder/yy3pbjummjlwi/before_m4_r8_and_after_m4