Sorry for resurrecting an old thread, but did you get it working?
I think what you have done is only added Artist (or Album Artist, whichever one you are using) as one step and told it to group by that. Which is fine, you get a menu of 26 letters. But you haven't told it what to do once you have selected one of the letters. If you don't specify any other items to categorise by, you'll just get a list of tracks in the last category you selected, i.e. all artists beginning with B. What do you want to see after you've selected B? The answer is a list of all artists beginning with B. What do you want it to give you after you've selected Beatles? A list of all albums by The Beatles. I think what you need to set up in your custom view is:
1. Album Artist (group by 1)
2. Album Artist
3. Album
So you'll get 3 menu levels to drill down.
1. A list A-Z. [You then select B]
2. A list of all artists begining with B. [You then select Beatles]
3. A list of all albums by The Beatles. [You then select Sgt Pepper]
4. A list of all tracks on Sgt Pepper.