No the distances do not have to be the same on either end. You do have to watch where your attachement points are relative to the hinge line though. A common mistake with pull-pull is to have the cables to tight or the attachment points to the horns in the wrong placed relative to the hinge line. You also do not have to have the cables parallel, I run them around corners, around obstructions etc. with no problems as long as you have a decent guide system.