Just like on MSN Groups, it's possible for a group on Multiply to have more than one administrator (that's what we call "managers" here) or assistant administrator.
Unfortunately, due to circumstances beyond our control, we're not able to migrate administrator status for any users other than the one who migrates the group. Sorry about that.
But don't panic! After the group is migrated, the group's first administrator (the one who migrates the group) will be able to grant (assistant) administrator status to the other members as appropriate.