I do use a common artwork folder, organised as My Music\Cover Art\$Group(<Album Artist>,3)\$Sort(<Album Artist>)\$Sort(<Album>)\<Album>_Cover.jpg, which works fine for the album cover.
I then put any other artwork scans in to the created folder, naming them appropriately eg Cover_back, booklet1, CD1, etc.
I can then go into Editing and manually "link to the original picture file", save, and all works well for Artwork rotation.
My hi-resolution Artist pics are organised similarly, My Music\Artist Pics\
But, I go to another install of MB (eg, my sister's laptop), and do a sync update of her files from mine. The the Album Cover and Artist pics show up on hers automatically, as I can set the file paths for "album cover storage:" & "artist pictures location:", however, I have to manually link all the extra artwork to the albums again via the edit screen.
What I'm wishing for is some way for MB to remember those organised links to extra artwork, across different installations of MB, just as it does with the Cover and Artist Pics.