Richard: I have found some bugs in the Mac 2.0b6 version. I haven't really been keeping up with things, so please forgive me if I say something that has already been said 100 times.
First of all, and this has been a problem for a while, is if you use unusual characters in filenames, they show up goofy in the playlist. Obviously not a big deal, but I do see it every once in a while. The one I see a lot is the bullet. If you want to see an example of this, hit option-8 into a filename.
Next is if you activate the "audio overlord" easter egg, the oscilloscope changes from a line into a bunch of lowercase g s. I'm not sure if this is intentional or not.
I just noticed today that NSF files will allow you to go 2 tracks beyond the end. For example, if there are 15 songs in an NSF, you can go to 16 and 17. Sometimes with different formats it will cause AO to crash when you go beyond the end.
That's all that I could find. But there's one last thing that I really wish you would do, even though it's not a bug. You know the little speaker icon that is next to the item that is currently being played? I made 2 new ones; one is for a selected item, and the other is for an unselected item. If you could implement a way to have both icons present and to use the correct one depending on if the item is selected or not it would make me very happy. Here are the replacement icons, in the same format (icns resources): http://benboldt.spymac.net/Speakers.rsrc.sit
I really think these icons would look better than the current one if you could find the time to make them work.