Rated 3 out of 5 stars
I installed Seamonkey 2.1 as an update on top off Seamonkey 2.0.14
Everything went flawlessly, SM 2.1 disabled Classic Default Theme 0.7.
So I installed Add-On Compatibility Reporter 0.8.5
I could now enable Classic Default Theme 0.7 and it worked, bur some things were badly broken.
Then I installed Seazilla Classic Theme 0.3
Seazilla works withh SM 2.1 and 2.2 after some tweaks.
Add-On manager OK, looks the same as the SM 2.1 Default Theme
Bookmark manager/organizer, some minor things but usable.
Password Manager OK
If you click Window/ Adressbook you get an anomaly. very wide bar
Culprit, the Delete/Remove Icon is not supported (verwijderen in Dutch)
It creates a lot of space, you can drag it from the bar, rightclick and
choose customize, drag it down and everthing looks ok.
I Used a localized SM 2.1 NL version (Dutch),Windows 2000 Pro, Seazilla looks grey-ish. I don't know how this theme looks on Windows XP/Vista/Win7
Sreenshots, (Dutch) Windows 2000
Adressbook wrong delete-icon (verwijderen = delete)
Drag wrong icon from the bar
Adresbook corrected after removing icon
The sync button can cause problems too.
Wrong Sync Icon in Browser
Sync Icon in mail/news