PostBox and iCloud - does anyone use pop mail for postbox and icloud? i can't seem to use my MAC pop mail with postbox.

Apple policy of reseting each time you forget an Account ID or Password makes it impossible for me to keep track of my many accounts on Mail. I decided to use PostBox and it's working great except for one account. That account is linked to icloud. I'm not too happy with icloud, in general, but I do want to be able to track my mail on my iphone for that one account (my business account). It used to be that I could use 2 accounts with one - using an alias. Now, I can't do that with icloud, nor can I get it linked to PostBox. Does anyone know what I should do? Am I asking the wrong questions?