Your loctite might be old and not curing properly. I suggest you get a new tube and re-try. I've had good luck with HPI's thread lock too. It's red in color and comes in a tiny bottle.

http://www.amazon.com/HPI-Pro-Thread...pi+thread+lock

I've placed the ball diff in both orientations and neither posed a problem. But usually I have the nut side facing towards me (towards left side of car) so that I can adjust it when I break open the halves as needed without taking out the diff.