Thanks Nick!
I've just downloaded and installed the extensions, I don't feel it has any problems so far, so it's all sweet now!
You'd better explain it better, what people actually need to do with your uploaded zip file is to "unzip" it, not just remove the suffix, I tried first by removing it and it gave an error, then I just right clicked on the file, chose "Extract Here" and then I dragged the ".xpi" extension file to firefox, then it installed it right.
Thanks again, I'm yet to see what improvements this needs to bring, I've already observed that the time it takes to firefox to load is much better, are there any other expected improvements?