BlueKey

1) Start Paint.NET 2) Draw something, e.g. use the paintbrush to draw a line 3) Add a second layer 4) Draw a line on the second layer 5) Choose File-Save As and save as Untitled.png 6) In the "Save Configuration" window, click OK 7) Now it asks if we want to flatten the image - yes 8) If we close the Paint.NET main window we're losing the layers I guess this happens because after the image has been flattened, the program thinks there are no layers... which is technically correct, because at this point there are no layers unless we unflatten the image. So it's probably not really an error within the program logic, but it seems a little counterintuitive to me (as a new user). When you choose to flatten the image from the menu (Image -> Flatten) it's more obvious you're changing the whole project, but when you flatten while saving, I would expect the changes to be applied to the output file only. For example, when you save as PNG it first asks you for "Bit Depth", "Dithering level" and "Transparency treshold" and, as far as I can tell, these settings have no effect on the main project. In my opinion, it would more intuitive to either do the flattening in the background instead of flattening the visible layers, or to do a temporary flattening by automatically unflattening the image after the PNG has been saved. In both cases, saving as PNG would not change the contents of the image editor, and Paint.NET would remain aware of the unsaved layers.

I think I'm having a similar problem. When I add layers, save as PNG and then try to *close* PDN, it closes without asking me if I want to save my changes. Since the changes have only been saved to a format that doesn't support layers, I'm losing the newly created layer information.