Here is a better trick for saving your css to joomla or any other cms which stores its css files as files(not in the db).

Load the development site onto your computer(localhost) using LAMP or *shutter* WAMP. And save the file to the actual css working directory, this will allow you to make multiple saves with the click of a button (no copy, pasting, then switching windows etc).

Check your changes into svn then update them upon next release.