Shawn,
The upgrade/renewal discount is only valid if you renew while your subscription is still active. Your last subscription looks to have expired in January, so unfortunately, you weren't eligible for the discounted price. There is generally less support for users who keep their subscription and extension up to date, and we try to pass that savings on.
As for your issue, JFBConnect should seamlessly upgrade your database tables. The error message your reporting though is indicating there is a problem doing so. Do you know what version of JFBConnect you were using previously? You also posted in the Joomla 3.0 forums, for which JFBConnect v5.0.0 is the first release for that version. Was this a site migrated from Joomla 2.5 (or earlier), or is this a brand new site?
Any information you can tell us about your configuration just before you installed JFBConnect v5.0.0 would really help us to understand the problem and help provide a solution.
Thanks,
Alex