Thanks for a wonderful app. I just started using Paint.net 3.5.5 and I had the same problem. You are correct, it was ATI Hydravision that was forcing the Tool windows to full screen. I simply added an exclusion in Hydravision for Paint.net and it works fine now.
1. Open Hydravision
2. Click Individual Application Settings
3. Click Exclusions
4. Click Add and Navigate to the App (mine is at C://Program Files/Paint.net/)
5. Select PaintDotNet.exe and Click Open
6. Click OK and close Hydravision
I had to manually re-size the windows the first time but now Paint.net opens and seems to operate normally. The Hydravision options no longer appear in the title bar but . . . whatever.
Thanks again.
