Anyone else having this issue? I was hoping the recent update would solve this but it hasn't. I find that the material room crashes Poser 12 a lot... Sometimes when deleting nodes, sometimes when changing maps, sometimes when linking/unlinking. I've lost many hours of work now to this issue, and now I'm saving every few minutes while editing in the Material room. There's also a bug when I drag and drop a texture from another window. Every now and then instead of creating a new node with the texture, it will not import the texture I was trying to drop but creates an empty node and it also leaves the thumbnail of the 'dragged' texture on screen. This 'ghost' thumbnail is persistant and stays on top of everything. Even if you minimize Poser, it's still there on the desktop or whatever folders you have open. I think it even stayed after I closed Poser. Refreshing the screen doesn't get rid of it either. The only way I've found to remove it is to create another new blank node and then drag and drop a texture into the new node. It doesn't import the texture into the blank node, but it creates a new node with the texture (like it should have done in the first place) and it gets rid of the 'ghost' thumbnail. Then I have to delete the blank node that I made. It's quite a pain to take all those extra steps....

Have you tried updating the drivers for your graphics card ? That may solve a lot of the issues you have described.

The thing with the "ghost" remaining on top of the rest was already present in at least the previous version, probably before.
My feeling: if Poser is occupied with the last operation (for example: disk I/O activities) it may miss something and create a empty picture node (and it takes some times, making me believe that Poser is about to crash...).
Then, when the host is there, restart to drag and drop the same picture file on the newly created picture node, so that your file will be accepted and the ghost will be erased.

This appears randomly, most of the time after many activities involving Python scripts (loading a complex material with many pics, for example)