I cannot use and load the high res maps and bump maps either with 512 megs of ram. What I found that does help is to resize the bump map jpg to 2000 x 2000 and then resave it as a bum file (back up your high res one first). Resave to the same name you see, so that your MAT and MAP files will work. This seems to be what crashes poser perhaps, bum files weighing in that large.