My Joomla installation is in a subfolder and I had problems with URLs. Contacted the authtor yesterday evening and he fixed the problem in a couple of hours. Thanks!

One of the best and simpliest extentions I have ever used. I had some complains but version 1.1 adds all the funcionality I needed.
You can post the button everywhere you want. Just edit the CSS file. You can also choose to show the button on the frontpage or not.