I have the same album rating field. Its very straightforward.
- Create a new User Field (Tools -> Options -> Library and Folders -> Manage Library Field)
- Name the field Album Rating (or however you like)
- Data Type: Integer, Relational: Store one value for each Album, Edit Type: Five Stars
- Check Save in file tags if you want that
No you can access a five stare rating album field in all the usual places. Bonus points, make an Album view that looks fancy: Go to you preferred Album View. Look above the Album covers you see a tab symbol, probably named "Albums" or something, with an arrow pointing down. click it and select "Thumbnail text". Then copy and paste the following:
<b><font color="5555BB">[Album Artist]<//font>
<font color="AAAAFF">[Name] [[Date]] <//font><//b>
<font color="DDDD00">Mid(★★★★★, 0, [Album Rating])<//font>
Attached screenshot shows how the result looks