Mercy! That was easy, even easier than the howto.
In Hardy Heron all you have to do is install wine from the repository. (I do have backports enabled, but didn't even bother to check which repository the download came from.) After that it's a double-click on the downloaded ImgBurn installer.
I'm going to let the Ubuntu community (and others) know that the best Linux burner was written for Windows. I've tested the crap out of it this afternoon, and it just works -- just like it does in Windows.
What a relief! I was getting pretty tired of fiddling around with the burners available from the repositories.