I've had problems with Adobe Photoshop LE refusing to load some JPEGs which came with poser downloads, but Poser itself (with the 4.0.2.118 Beta patch) has handled everything I've thrown at it, including those JPEGs. Paintshop Pro opened them too. I have had to kill Poser once since installing the patch a week or two back, when it sat for five minutes doing nothing and not responding to mouse or keyboard at the beginning of a render; but it can take so long to start rendering complex scenes on my machine that I don't know whether the software had locked up for good or was just thinking extra hard!