I know almost how you must feel. I had to join my accounts yesterday, too. So, I logged into STO (I'm a lifetimer, too) and followed the instructions. I tried to log into my Cryptic account but ended up getting into my PW account - where, no surprise there, there were no Zen points and no lifetime account.
Well, I was stunned... somehow I must have used the same email-adress and nickname for both accounts. There was no way I could link those accounts on their website. So... I sweared a lot, smoked half a pack of cigarettes, sweared some more and started the launcher again. I logged in, the same information page appeared but this time I just pressed next. Well, there I got asked if I would wish to link my accounts...
Personally, I found the thing overcomplicated and is possibly very prone to bugs.