Some suggestions:
1. Check the spring bar weight rating. they SHOULD be at least the fully loaded weight of your trailer tongue. If this is not known, then use 15% of your trailers GVWR as a minimum spring bar strength.
2. If you are not transfering enough weight (that would be indicated by the rear end sag and front end lift) you need to tilt the hitch head toward the trailer (tilt it back). This will make the ends of the bars closer to the ground and make it more difficult to latch up the spring bars. You SHOULD find it necessary to use the trailer tongue jack to raises the hitched tow vehicle and trailer about 6" to a foot in order to be able to latch up the bars. When the tongue jack is retracted again it will put that tension onto the spring bars.
When the correct spring bars and adjusted correctly there is NO reason to use air bags, helper springs etc. Those items will do nothing but prop up the rear of your tow vehicle and will do nothing to improve the handling or ride of the towing combination.
The MEANS of tilting the hitchhead are varied depending on the equipment you have. Generally it is done by adding or subtracting washers behind the hitch adjustment and re=tightening again. SOME hitchheads use an eccentric tab that is rotated to different positions to cause the hitchhead to tilt differently and some use a threaded bolt which is tightened or loosened to change the angle. Without more information about YOUR system I can't comment on how yours works.
Fords LATEST recomendation for setting up weight dist systems is to replace one half of the rise in the front of the vehicle when hitched up. Measure from the fender well to the ground before hitching up then again afterward and split the difference due to adjusting the hitchhead.
The GOAL should be spring bars that are approximately parallel to the trailer frame (when latched up with weight on them) so choose the chain link that accomplishe3s this first THEN adjust the tilt to get the weight transfer correct.
Good luck with the new set up. Doesn't sound like your dealer did you any favors by providing a hitch with no instructions or without properly setting it up for you.