I just tried it and what happened was that avast! put it in the auto sandbox with a red border around it. The analyzing popup came up, said it didn't find enough evidence to consider ImgBurn to be malware and then terminated it. The popup window stayed open with the options to either run it normally or in the sandbox next time. I chose to run it normally and now it works fine with an exception having been added in the sandbox settings.
This is how it now works but, it will not work correctly if you are running the avast! gadget. The gadget prevents sandbox exclusions from being properly created so if you are running it, turn it off. If you do not have the gadget, then set the auto sandbox to auto and you should get the same behavior that I outlined. The exclusion should get created and then ImgBurn should work fine.
I hadn't opened ImgBurn since updating to v7 so I didn't know that avast! now considers it suspicious.
