I have the same problem as Sylvain. I have installed the block into my blocks folder and get nothing... it doesn't show up in the admin area at all (not premarked as invisible or anything...)
The really strange thing is that I installed it on my development server (MAMP) on a laptop and it works fine???
I'm running 1.8.4+ on Ubuntu Linux.
I'd really like to use this but don't even know how to start troubleshooting it since I'm getting nothing....?
Any help will be appreciated.
Jason