The Punisher

Is explained in the first post.

The model is "too high poly" (too "detailed") for JKA. https://jkhub.org/forums/topic/10304-whats-the-general-vertpoly-limit-for-a-model-in-jka/?tab=comments#comment-143842 https://jkhub.org/forums/topic/4912-help-run-out-of-transform-space-for-ghoul2-models/?tab=comments#comment-72255

In blender, select the mesh, go into edit mode, make sure the entire mesh is selected and press CTRL + N. Exit edit mode and export the model. You might still a two sided shader if the inside of the mesh shows transparent from certain angles.

Tried the model in different maps and couldn't replicate the issue: I added new speculars, if that doesn't solves your problem, you will have to figure it out on your on. Also, tweaked the textures a little more (didn't had time to work on the "pants" on the previous one) and merged it with the original model so you can now swap versions.

The included screenshot is from the game, what is exactly broken?