Oh yes, Vue 6 Inf works fine w/Poser 6.  

One thing I picked up in another post, and it has helped.  In Poser 7 under Preferences -- Render Options, I increased it from 1 process to 2 processes, and as separate threads.  I have a dual core Pentium.  That helped immensely, and now I am not sure but that performance is back to equal that of Vue 6/Poser 6.  Haven't had a lot more time, but will do some more testing in the near future, I expect.

But that may have made the difference.