well.. when you posted there was only one question:
Ok in this mode, if i change password of a user on domain server, do i have to change the password of the same user on the accountapp computer?
and I answered "yes, sure"
you edited your post adding another question..
there's no (easy/available) sync feature between 2 or more SME servers.. each time you create/edit/lock an user on the "main" server, you have to replicate the same on the others.
hope this is clear enough now