Hmm, I've been having the same problem, for about a week... and I KNOW I've never set it to open automatically... Guess I'll check it's settings, thanks for the advice, Thorn.

Suggestion: load and minimize task manager, so you get the CPU graph in the system tray. I will bet that your system is pegged at 100% CPU when running the larger (not size, more object intense) render. It's helped me get over a lot of the Poser "freezes", doesn't make it faster, but at least I know it is doing something. I always have it running when rendering, calculating dynamics, adding INJ and Morphs. And Poser is not consistant with handling interrupts while doing intensive processes. Some actions register a cancel immediately, just take a while to quit (rendering scene AFTER loading textures and making shadow maps), or never even notice (while loading textures or calculating dynamics). It is faster to flip the big red switch on the back of the building than to try to stop Poser while calculating frame draping of 8000 count hair! =P The bane of Poser 5? Dynamic hair, OMG it sucks to render! Even worse, try doing it WITH a shadow map, with multiple lights! AAAAAGHHHHHH!!!!! I've also had a lot of failed renders (Firefly just stops, drops back to Poser with partially rendered image) with Dynamic Hair. (Sorry, got off topic there)

Python is an open source programming / scripting language. You can get it: http://www.python.org/download/ In theory, you would just install this, and not Poser, and your scripts should up and happy, unless of course, CL modified gasp their Python compiler.

I don't think it is a bug. I've been playing with dynamic hair recently, and calculate dynamics with collision on takes a lifetime to run. I suspect that when you load the prop (or character with the hair), Poser tries to recalculate the hair. When you import the file, it does not. I made two CR2s, one with dynamic hair and one without, and there is a HUGE difference in load time between the two.