In my admin it says that I can't install any themes because the "themes" folder isn't writable. I checked and it is writable for the administrator but not goup or public. Isn't that how it should be?
It should be 777, the package manager in 1.1 has a permissions cleaner which allows you to chmod all files or others :D
You need to log into your server through ftp and chmod the forum files to 777