The 6.5 Sprint ROM has issues with the Facebook album (I'm assuming you're talking about HTC Sense) and it does not have to do with any .dll files. It has to do with a few registry entries. Just in case you don't know, the Facebook app you speak of that's by Microsoft has nothing to do with the Facebook integration with HTC Sense in the phone. I do recommend going to a custom ROM, since it will have the Facebook fixes built in, and will have the newer social networking packages (most likely).
Go the to following thread and follow the steps they mention in the first post:
http://forum.ppcgeeks.com/cdma-tp2-d...w-hardspl.html
After this, you should be able to flash the custom ROMs that are on this forum. I usually try to make mine simple and straight forward to install and so do most others.
Hope that helps!