I currently have FCG running wonderfully on about 10 websites, wordpress 2.8.5-6. Today I had an issue with FCG just activating on a new website, which I cookie cutter to get them quickly. I shut off all plugins, started FCG and found that a wordpress plugin "them my login" ver 4.3.2 was my stopping point.
Now I have both of these running on some of my websites together, maybe diff versions of all parties, but at the moment I need to continue working on my websites. So hopefully this helps some tired developer a few minutes of headaches.
FCG is one of my main gateway to sales with rotating picture ads.
Peace
Bill
www.cleaningjettedtubs.com