I've tested it with various modloader mod. When many texture are added by them, it override the Torso Leather armor gui texture.
This doesn't happen when i use modloader.
I've switched to modloader only for test purpose. The two did not get installed at the same time.
Im using MultiMc
It is a small issue, i know, but i wanted to let you know. Thanks for your time and forge is awesome. Thanks for what you do
Here the code