Hi Mike I see - I had just heard you mention your old machine before, and since the kind of thing you're showing there is going to consume a lot of memory it might require an upgrade on an old machine in order to not run out of memory too easily.

Possibly on your new machine it's not so much running out of memory that makes things exponentially slower when more pieces are selected - probably when you start selecting some of the shapes that are approaching the pole area of the revolved surface it could be possible that those ones are taking much longer to process because of trying to deal with the compression or expansion of 3D to UV space that occurs around those areas of the surface.

- Michael