Hi. Legs and skirts move and morph differently. If you were to transfer data from legs, you'd see why: the issue would most likely go away, but the skirt would behave weirdly between the legs. When a properly adapted skirt is too close to legs, they clip into each other, which is one of the reasons we remove a body area covered by a garment. Since you cant remove too much of it in the leg area, you need to make sure there's space between the two.
See how much tighter your skirt( orange outline) is compared to the maxis one?
Other issues:
- skirts are vertex painted with two colors. It is best to transfer vertex paint.
- from MD export the garment as weld;
- remove doubles on the body;
- if using md buttons, remove threads, delete the underside and the inner side of holes, collapse holes before decimating;
- shadow map must have white only where the shadows are, not everywhere. This worse,s the quality of other items a sim wears;
- before baking textures, check how a garment behaves in game first to not re-do everything like you're going to have to right now.
How to transfer everything, including vertex paint