Eitehr it's merely buffer corruption because you exhaust your hardware acceleration resources or something with PS' tile caching in general. Also, do you actually always apply the transform by hitting enter? Some system info might shed further light on this...
Dear Mylenium:Thanks for the reply. I'm on a fairly new iMac w/ 16 GB of RAM, running 10.8.3. And yes, I do hit "return" before I switch to the second file. I commit the transformation, so that, for example, the item on layer 3 rotates 90˚, or whatever, then I click on another file also open onscreen. When 1've maybe copied something there and go back to file #1, maybe 30 seconds later, the item on layer 3 is back in its pre-rotation orientation. So far, I don't recall whether the reversion goes back farther than one step-meaning that I can't recall if, after I rotate, then change scale, then flip the item horizontally, whether the reversion takes it back only one step or all three, but it reverts at least one step. So how do I fix buffer corruption, poor hardware acceleration, and file caching? All I know is trashing the prefs, and that doesn't help here. I think there's a cache setting in the PS prefs, but changing hardware acceleration and buffer corruption preoblems-dunno. Is there a knowledgebase article on those issues? And what is there about CS6 that makes this happen, while it never happened in CS5 or earlier? Greater demands on the hardware?
This is still happening in PS CC. It didn't at first; now it does: I have, say, four files open at once, I make a change in one, e.g., pasting in something from Illustrator, I position it, then shift to another onscreen tabbed file. When I come back to the first one, the pasted-in part is gone, no sign of it, even in the History pallet. Granted I'm not losing much, but the solution isn't always as simple as just re-pasting from the clipboard. Sometimes it's brushwork done on the image. It's annoying. Any ideas? I'm on a 2.5-y. o. iMac, running OSX 10.9.1, with 16GB of DDR3 RAM and a 2.8 GHz Intel Core i7. It seems to have started in PS CC around the time I upgraded to 10.9.1, but that may not mean anything.