I was able to get this working fairly easily. Including LDAP groups.
You will need to either create a user to access the LDAP with or use an existing one.
Follow the OpenFire instructions to connect to Active Directory. The only odd item was the Administrator DN. I found you have to use the full name not the username. I have a user named Open Fire but the username is OpenFire so the DN is CN="Open Fire",CN="Users",DC="YOURDOMAIN",DC="LOCAL"