I really like the flexibility you have now given us with respect to the Album Artist field, with or without (auto). But I have a couple of questions.
Is it possible to use the Album Artist field in path and file names? For example, using the 'Tools>Rename File from Properties' dialog. Ditto 'Tools>Fill Properties from Filename'.
Using either [Album Artist] (with a space) or [Album_Artist] with an underscore doesn't seem to work.
Also, could the pull-down list of 'rules' in that dialog 'learn' from different rules typed in by the user?
For classical music I have been editing the directory rule in the above dialog to [COMPOSER]\[ALBUM] - it would be convenient if new options like this appended themselves to the pull-down.
I guess this would be equally useful in other dialogs, like the Burn CD 'Option>Rearrange CD folders'.
Actually thinking about it as I develop this posting, I note the dialogs for 'Rename Files from Properties' and 'Rearrange CD folders' are quite different. Why not use the same model?