Yeah, unfortunately it cost me 22,- EUR. But for me, it's worth the money. Please read the forum of frontpageslideshow before you buy it. There are some people seeming to have problems with the script. Its natively written for Joomla, and it seems that its people using it on Joomla, who a experiencing the errors.
I tested my blog on IE7, Safari and Firefox and I do not get errors, so for me everything is fine. If anyone of you gets errors on my page please tell me your browser and OS Version.
Support from the guys who develop FPSS does not seem to be very good. Normally a behaviour I don't like, but as I said before fortunately for me everything works fine.
Once you bought the script its almost self-explanatory. Just delete the ui-tab call in the index.html and replace it with the slideshow-call. Some CSS-Adjustments and settings in the fpss.php and all is fine.
One major customization I did was that I changed the FPSS.php so that I dont have to fill in the posts I want in my slideshow manually but they are pulled from the_loop automatically if they are in a certain category. And I use the_excerpt and the_title and the custom field (leadimage) so that all is put automatically to the slideshow. Was all pretty easy even without programming knowledge (which I dont have ;-))