"How do I keep the groups and get rid of the materials in UV Mapper?"

Open UVMapper (I only use classic, for creating templates and quick operations such as this. Otherwise it's buggy in regard to high poly/high # of groups models. I've had it omit polys from groups before. For templates and .obj chopping operations it works fine. I assume classic and pro have basically the same export options).

Open your .obj in UVMapper.

Go to file: export model. Uncheck Export: single group, usemtl.

Save your file. UVmapper will chop out the usemtl tags. You'll have a single material with an arbitrarily assigned color upon import to Poser. Preview. There's no way around this... your model would be invisible otherwise.

As far as doing this all within UVMapper pro without export? Dunno. Select: Material: Edit: Delete?

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