Install

1. Download both zips. Don't unzip them.
2. In Blender go to Edit > Preferences > Get Extensions, open the arrow menu in the top right and pick Install from Disk. Install ugc_checker-1.2.1.zip, then ugc_recolour-1.2.1.zip. You can also just drag each zip into the Blender window.
3. In the 3D Viewport press N and open the UGC tab.

UGC Checker & Exporter

1. Select your model.
2. Pick the item type and body scale (Normal, Slender or Classic). The size box shows in the viewport.
3. Press Check Model. Problems show in red, warnings in yellow.
4. Press the fix button under a problem, or Fix Everything.
5. Turn on Live Check if you want the box to update while you model.
6. In the Export section pick a folder and press Export for Roblox. Tick Texture PNG to also save the texture.
7. In Roblox Studio import the FBX with the 3D Importer (scale unit: Stud).

For layered clothing, name your cages _InnerCage and _OuterCage and parent the mesh to an R15 armature.

UGC Recolour Batcher

1. Select your model and click the eyedropper to load its texture.
2. Pick a mode: Shade, Hue or Colorize.
3. Add colours: pick a colour set and press Add Set, press Random, or pick colours from any image.
4. Press Show on Model and click colours in the list to preview them. Press the back arrow to go back to the original.
5. Choose the output folder and texture size, then press Make Variants.
6. Press Lay Out in Scene to put all colours side by side for thumbnails.