Adding a extra HD should be no problem but I don't think that is the solution to your problem. The problem is the memmory isue and a the CPU. It's pretty cheap now to upgrade your computer.

There should be no problem using this combination in Pro Pach since you only are using image maps. If you want to use reflections like reflecting the surroundings in an object you have to use Poser 5. There is a tutorial in here at Renderosity on how to make a fake reflections in Poser 4 but it's prety complicated. klapakling

I have the same problem with the firefly render engine. I think it's a bug in the program. Have you tried to decreas the quality setting on pixel samples? Try to use draf setting and 3-6 pixel samples. It seems like the more complex the scene is more likely that poser will crash. I usualy render my images at 2500 x 1500 pixels. When using raytrace there is a higher risk that Poser will crash. Be sure to reset all the lights when you apply a new light preset or Poser will crash to. klapakling