Payload ending problems

As mentioned in my introductory post, I'm working on a Payload map, and I have a couple of problems with the payload itself. Most of it works (thanks to the Gametype Library) but it seems the end is the problem.

1) When the cart approaches the final point, it seems to activate an environment shake on some of the path_tracks, but there isn't anything on their outputs. I've checked for collisions as well. This happens regardless of whether I'm sitting on the cart, pressing up against it or at the limit of its capture zone.

2) When the last point is captured, I want the cart to go down a short slope before falling into the pit. I've moved the relevant outputs for dropping the tracktrain to the path_track just above the pit, but despite various attempts, upon reaching the actual point the round is won, and the train stays put instead of moving off again through the newly opened doors to the pit. I have connected the path_tracks.

These are the outputs on the capture point path:

OnPass - sspl_pushzone - CaptureCurrentCP (included with Library)
OnPass - cap_door - Open (Opens the doors to the pit)
OnPass - sspl_pushzone - Kill (An experiment in case players in the pushzone interrupted the move command)
OnPass - sspl_train - Resume (Another experiment)
OnPass - cp_four - Set Owner [3] (included with Library)

And the ones I've moved to the pit:

OnPass - sspl_carttip - PlaySound
OnPass - sspl_flashinglight - Stop
OnPass - sspl_constraint - Break
OnPass - sspl_train - Kill
OnPass - sspl_cartbeep - PlaySound

Interestingly, I have now done that to the path_track; it now proceeds to continue along the track at the same speed that it was at the point of capture (i.e. I'm testing it with a Scout, and it continues along the track as if there was a Scout pushing it). Something to do with the acceleration there, probably. And as for the rumbling - I think I know what it is now, and it's a stupid mistake I made earlier if I'm right.