I've just paid and updated your plugin to the last version (2.6.4) and everything stopped working.
My comments on Facebook do not import anymore to my site, the autopost to Facebook posts directly to my wall (and not my fanpage anymore), and the Facebook API page, the APP ID sometimes CHECK but sometimes FAILS to.
Since I've paid for this upgrade and everything stopped working, I will expect full support on fixing this. We have paid customers for the next month who are counting on this integration with Facebook.
My website is vgBR.com and I can provide you an user for wordpress for you to check if necessary.
Thanks in advance and awaiting your reply