Firstly, J. Great work!
It took me forever to find out how to enable the social networking engine but finally here's what I did.
I am running 405H.
1. Installed "HTC Album + Social Networking Engine" from
here (this may or may not be necessary but will allow you to post pics to facebook!! VERY QUICK and SIMPLE)
2. The trick is getting Facebook signed in and that is found under "Connections" in "All Settings". Click on "Account Manager".
3. Provide email and pass and ..... Voila!