If you're familiar with the .obj file format then the following will make sense... For a morph target, the Facets (f lines), Normals (vn lines) and UV coordinates (vt lines) are completely ignored. The only thing used out of an .obj file for use as a morph in Poser are the Vertices (v lines). So, I'm not familiar with RDS, so I can't help with 'how' it's happening, but 'what' is happening is pretty much exactly what that warning says... you're ending up with a different number of vertices (probably more) than the original mesh/object. You can verify this by loading the two .obj files into UVMapper and noting the various counts/stats displayed when it loads. Good luck.

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