If you have having difficulty why not raise an issue on GitHub (https://github.com/raburton/tabscroller/issues) and I can try to help you with it. Perhaps you are using an untested platform for which I can add support, but you have not provided any information at all in your review to help identify your problem.

Update: Why not raise an issue on GitHub and we can have a discussion, this isn't really the best place. A good starting point when opening an issue would be to include what version of Firefox you are using and what platform you are on.