I am a complete beginner in creating CAS (Create-A-Sim) content, particularly clothing. While I have considerable experience in creating build and buy items, I am now focusing on learning how to create clothing items for The Sims 4. Currently, I am attempting to convert a top from The Sims 4, and I have received permission from the original creator to do so.

So far, the process has been going well, but I encountered an issue where one armpit of the top appears black, as if the sleeve is not properly connected to the rest of the garment. I am using mesh toolkit to assign bones, but I’m not sure what’s causing the problem or how to fix it. If anyone has insights or solutions regarding this issue, I would greatly appreciate your help!

A couple of things, I can think of off the top of my head can cause that... but just guesses, without seeing the work. If you did, duplicate and mirror in Blender, the normals are probably reversed. If you have a doubled mesh, TSRW may show as black, if the inner and outer meshes are close together. Could be no UV mapping of that part.

Easy thing to do, is upload the work so it can be looked at.