If anyone's wondering, I gave up on Material Manager. Deleted it from my computer and asked for a refund. They were very nice about it, and returned my $$$, no questions asked.

If it really did let you "shift on the fly," I might have kept it. But it didn't. It would look as if the colors had changed, but if you rendered, the old colors would be there. Or if you went into the Material Room to add some nodes, DOINK! The old colors would come back. The only way to make the new colors stick and actually render was to make a MAT pose, save it, and apply it. That being the case, I decided I might as well just use MAT Pose Edit and Poser 5 MAT Writer for free.