Rated 1 out of 5 stars

I have tried this and that, have read and re-read instructions, and keep going round in circles.

This review is for a previous version of the add-on (2.61). 

Hello!

There isn't much magic in the process:
1) right-click in the "add to Firefox" button;
2) Save the file to the hard disk;
3) Open the target folder and drag the file to the Desktop (or save it there directly);
4) Open Firefox and go to the menu: Tools > Add-ons;
5) Left-click in the downloaded file and drag it into the Firefox add-ons window;
6) Accept the installation;
7) Right-click in an editable text area, for example: try it here when you are going to increase your rate to 5 stars, Select: Languages > English (United Kingdom) in the pop-up menu.

Voilà!

Not much magic in it.

Please try it and send me a private e-mail if you need any further help.

EDIT: If you have already the GB speller from the other guy, you need to remove it as it will conflict with mine.