I'd like to integrate Facebook login options to my SMF forum, however there are some questions I couldn't find the answer for.

1) Can existing members link their forumaccount to their Facebook profile? I don't want to end up with hordes of members creating a doubled registration. If yes, can they choose their method of login (regular or social)?

2) What happens to the accounts created with the mod when it is uninstalled?

3) Can this mod be used with custom themes?

4) Is the purchased license valid indefinitely or does it require annual payments?

Sorry for the many questions