Mousso,

I suppose the one obvious idea that escaped me earlier would be to try another character skin and see if the issue is limited to the one character. 

If so, texture problem. If not, settings problem :-)

Beyond this, I would suggest to see if you have a random shader set on the skin that isn't present on your other textures. Awhile back, I had a test character look like it's head exploded in Lux but rendered fine in Studio. It took me a few dozen renders and material checks to finally figure out that I was a complete clot and missed a displacement map. 

On the other hand, if you're running Studio 4.5, well, good luck to 'ya!   (By my own admission, I haven't upgraded beyond 4.0.3.47 for various reasons. I may, eventually!)

Good deal on the shoe fix though. I use SubD and mesh smoothing a lot more than I used to, which may have subsequently fixed my jaggy issue by random coincidence. Whoops! 

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