When I upgraded to 8.01 I lost the ability to log in to sites using my HP Simple Pass finger print scaner. Is there anyway to fix that?

Check under Tools -> Add-ons to see if the Firefox update disabled the extension for compatibility reasons. If so, notify HP so they will update their extension.

It is actually my TrueSuite Website Logon 5.0 that is not compatible with Firefox 8.0.1. There is not a new one available yet. Is there a way to down grade Firefox to what I previously had?

Try instead the add-on Add-on Compatibility Reporter. This add-on will allow you to enable and test an add-on that is not known to be compatible and report back your experience. Some add-ons function acceptably with forced compatibility, and some don't.

Going back to a previous browser version will open you up to security problems. There are other add-ons that might replace the functionality of the one that is a problem. See:

https://addons.mozilla.org/en-US/firefox/extensions/privacy-security/?sort=rating

Please mark this issue as "Solved" if it solved your issue, or post back if it did not.