Well, Poser likes lots of memory on a Mac, I hope you have at least 128Mb, 256+ is better, there was a thread not to long ago where somebody called Curious Labs on the Poser memory settings, they suggested 150,000 minimum, 300,000 prefered (pick application after installation, pull down File, Get Info, Memory, must be set while not running), that seems to work better than anything I've tried on my G3. There was a plug in for Poser 3 in RD5.0, it doesn't work with 4. I assume it let you open Poser from inside Ray Dream Studio, so no big deal.