Asking this in behalf of one of my friends. He wanted to convert his account to Steam, but apparently his existing account was with a facebook login and he couldn't log in to the steam-based client using that account. Do you think he might have been doing something wrong, or is there no way to convert from a Facebook Account directly to a Steam account without him starting all over again?
As far as I know, a facebook account is just a normal account, so he should follow the steps posted by the devs in the annoucements section.