The main thing I use Paint Dot Net for is editing Textures for Minecraft. I have one file with layers for all the different ore textures and stone textures I've made/borrowed (with premission)/altered, and when I need a new one, I copy the layer, save the base image as a ".pdn", then save as a ".png".
At this point is has about 80 layers, and the .pdn is nearly 2 megs in size. I wouldn't think it would be a problem and prior to the last time Paint dot net updated, a save operation took about ten seconds.
Now it is taking upwards of ten minutes.
Help?
EDIT: First off, version is 4.0.5288.36565
Secondly, may not be so much file operations as a file operations which involve changes in numbers of layers, IE: opening a multilayer file, or merging layers to save. copying and adding layers does not appear to cause any problems.
--- if interested: Eben's Ore Texture Pack