Hello, once again I have a issue. I imported the YPlum mesh for rump to shoeswap. I got it looking good but when I go to export it has there are unassigned bones. I did just cut the legs off the other and import the boots as a wavefront object. I will include file like always. They are not regrouped in this version yet.

Go to Joints menu. Click "Draw vertices with bone colors". Anything showing up white is unassigned. These parts will behave strangely ingame, and need to be assigned to their respective legs.

Wavefront (OBJ) doesn't keep bone assignments, and on occasion I've also seen it screw up UVmaps for clothes and hairs (puts them one square lower, which can cause issues with clothes), so best stick to the "Sims2 Unimesh" formats (Export and Import). If you don't already know (I'm guessing you do, but better safe than sorry), in SimPE you extract a mesh with joints by right-clicking the GMDC and clicking "Export".

If the mesh already exists as assigned for TS2, you have to export and then import as "Sims2 Unimesh" format to keep the bone assignments. Answer "no" if you get a question to import a second skeleton (don't answer yes, or you risk messing up the mesh!).

If it doesn't exist as assigned for TS2... Then it's probably a good way to learn how to do it. Legs are fairly easy to assign manually as long as you keep track of which leg is which (I import another assigned mesh as a guideline, marking a vertex on the already assigned part, clicking "show", then selecting the correlating part on the unassigned mesh, and click "assign". There's some auto methods to do this, but I've never gotten them to work properly (most have a tendency to do a shoddy job imo...). If you have the "TS2 Unimesh AutoJoint v4.09" - I think it's part of the UNimesh tools - it kinda works on the legs, but I can see some potential problem areas around the ankles, heels and a few other places, so some cleanup might be required. Not the worst I've seen, though.

It worked! But now I need to remake the textures. See ya in that forum haha

*Edit, I went into game and the legs are not lining up they show assigned in milkshape

Here is the new milkshape, regrouped with all vertices assigned

Sure you replaced the mesh? And deleted cache files? You also need to make sure the seams (or where they overlap) have the same bone assignments, or there will be some clipping.

The mesh looks mostly alright, but there's areas on the inside of the calves where you (with show colors ticked) can see a somewhat orange area in the green, and a brighter pinkish orange in the pink area. These mean those vertices are partly assigned to the wrong leg. You'll want to set them back to 100% for the proper leg. This often happens if you use the auto tools, so you'll usually have to make sure everything looks alright before exporting.

My best tip for this is to save the file, then click the Anim button. If anything moves, it's not assined 100%.
Choose Rotate and Local in the In the Model menu, go back to Joints menu, click "Show skeleton", and double click the joints you want to test in the menu (thigh, calf, foot, toe - both sides, they're a little below the middle of the list). Bend, stretch, and move them around. If they move the way you want, then they're most likely assigned correctly. If there's weirdness, or the wrong parts of the mesh move, you'll have to fix that (but it's not a good idea to save the file you've animated, because this can occasionally cause issues. You can have 2 MIlkshape files open, though. One for animating the joints and one for fixing. Don't save or export while in anim mode (this can screw up the mesh). Anim mode is activated when the numbers beside the button are editable. If they're greyed out, Anim is off.