I’ve seen this issue with one other user. I’m not sure why the copy did not work, but for him, we ended up copying the files by hand - here is the procedure:
Open the TotalSpaces2 DMG, then run the Uninstaller. Then drag TotalSpaces2 into the Applications folder as normal.
Before running TotalSpaces2, open a terminal window, and paste in this command:
sudo cp -r /Applications/TotalSpaces2.app/Contents/Resources/TotalSpaces.osax /Library/ScriptingAdditions/
(It should ask you for your password, and maybe also warn you about being careful if you haven’t used sudo before).
Then run TotalSpaces2 as normal from Applications, and hopefully it should work.
Let me know if it works!