Ever since I upgraded to 3.5.1 Paint.NET will crash when I Ctrl+Z from a flatten. It doesn't happen every time but enough to be very annoying. I've been using Paint.NET for a while, and it's been for-freak-ever since I've had any hardware updates, so it seems like it's a 3.5.1 issue. I don't believe I have any plugins (at least, I haven't installed any recently enough to remember).
The file I'm currently working with is only about 1.3MB at the moment and has 6 layers, nothing overly complex.
EDIT: If this is related to the "out of memory" sticky topic, what the heck am I supposed to do with that information? It doesn't happen every time though, which it probably should if it's running out of memory. What I do is make a small edit, flatten to jpeg (it's a texture for a game), view the texture on the model, un flatten, make another small edit, rinse -> repeat. Sometimes it works, sometimes it doesn't.
pdncrash.log