Quote - Not always true - I've had trouble with some partial MAT poses not working in Poser 6.

Partial MATs don't work with nodes, which means they're not compatible with P5, P6, P7 or PPro.
A wacro (or some other script) needs to be used to achieve the same affect (which means P5 is much more difficult to work with in this respect, due to the lack of Python access to shader tree nodes).