UV Mapper can also assist with your Grouping issues, but don't be too frustrated that your Groups aren't following your topolgy exactly...once you become proficient with rigging in Poser you realize how Grouping really doesn't have to be an exact science, the MatSpheres really assist with that sort of thing.

The thing with shoes is if you just have a Foot bone (like Phil has suggested) you can still bend the toes via a dial, however if you have a Foot bone and a Toe bone you will get a nasty poly shading at the Foot/Toe joint...not good.

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