Had a similar problem, and (unfortunately) it turned out to be a tremendous pain in the ass. I got the diagrams from the dealer as well, but they were not very helpful. After hours and hours tinkering around down there, I think I finally began to understand how those seat mechanisms work. It's basically all about the three cables (one for forward back/one for up/down/and one for tilt) and how they attach to their respective small knobs.
My guess is that you popped the cable off it's catch knob.
If that's the case, the good news is that the forward back is the easiest to get back on. You just need to find the associated knob (perhaps from the schematic) and hook it back on. Trick is finding it. Also, there is a chance you snapped it, in which case you'll probably need to get a new part.
Good luck. Sorry I can't explain any clearer.