Hi everyone, I am very new here but has been wanting to make a game with my imagnation .

 Currently I found this EF-12, and start to learn thins. But  I am trying to export model from Blender. Thing is very good without bone but when I export with bone, some part of mesh disappear? Anything hint?

The problem is when I use foolviewer to check, I saw the object shadow is good, not missing any vertices??? Is there any problem with UV texture or bone wieght here?

Hope to have some help