What did you put for the path? I found that, contrary to the instructions, there was no default -- I had to specify "/" (or /saver/ etc.)
When it can't activate your selected saver, it uses the default download save mechanism. Once the GH saver works, it stops
saving to your download directory.
The smoothest way to use the GH saver would be in conjunction with github pages. With GH pages, it works a lot like tiddlyspot. Without gh pages, at the start of each session
you will need to download your last saved copy from GH to your local drive, load it into the browser, and set up your password. The problem with GH pages is
that everything is public.
Good luck!