regarding sweep i put my group on wait somewhere away, killed monsters on my own with sweep and got no xp, tried it several times so something might be off.
Yep you do. The xp you get for each kill depends on how much damage you did during the fight. If you have a big group all well equipped then you'll kill monsters much faster but your share of the xp won't be as much (there is a multiplier to partially compensate for larger groups, but it never gets up to the same as if you could kill everything on your own).
I'm unclear about something, If i conquer a territory that still has survivors, do they auto-join or do i need to recruit them first, then get the territory?
That sure sounds like a bug, I'll look into it.