I had no trouble at all importing those BVH files to see what they would do. My system specs are OS 9.2; Poser 4.0.3 with ProPack SR 3; 384 MB RAM; 10 GB HD; iBook PPC G3 500 MHz. I have also upgraded to OS 10.1.3 in another partition, but I never run Poser under OS 10. In fact, the only time I use OS 10 is for Bryce 5.1 (the upgrade is at Corel's web site), because it renders about 3X faster than under OS 9.2.