When an earlier version of Fusion (2.0.2 I believe) broke driverless printing for me, installing 2.0.3 fixed it. Installing 2.0.4 broke it for me again (well, I don't know that for sure, because I did some OS X software updates in there as well). 2.0.5 didn't fix it again by itself, but using the Fusion uninstaller and reinstalling 2.0.5 from scratch took care of things.
I thought I'd pass this along in case it might be of help to someone else.
Out of curiosity in any of those scenarios had you attempted to reinstall Tools first rather then all of Fusion?
No, I didn't try that. Maybe that was really the trick. But it wasn't so difficult to uninstall/reinstall Fusion.