auto reverse loop using AD520

My son wants to run his trolley back and forth on a single track. The model dealer here said the AD520 would work even though he has only a standard DC track with the standard control box that comes with "simple" train sets.

Here is how I was instructed to connect it. If you are looking at the track from left to right.

1. Far left end has the power going to it that controls the speed of the trolley. One wire to each rail.
2. @ 8 inches toward the right we have two red wires, on to each rail from the AD520. To do the reverse, I was told I need to branch these two red wires to the other end of the rail, so I have two wires going to the far end of the rails, all the way to the right.
3. I have clear plastic isolators @ 2 more inches to the right.
4. @ 4 inches past the plastic isolators I have two yellow wires going, one to each track, from the AD520 to the isolated track. These are the only wires going to the "middle" part of the track. In other words...Left track- isolator- middle- isolator- right track.
5. Then @ 8 feet to the right, I have the final set of isolators and then @ 12 inches of track that is connected to the AD520 via the red wires that are branched to the left end.

so what I have is:

left to right

power- track- red wire from ad520 - isolator- track-yellow wire from ad520- isolator- track- red wire from ad520

Problem- It isn't working

1. When I put the train on the track, the ad520 makes a rapid clicking sound.
2. When the train does move on the center track it just jurks back and forth, which corosponds to the clicking of the ad520.

The instructions state no to use with standard track, but I clearly told the model supply store I only had standard no DCC etc, and they stated they sell these all the time to do the same thing I am trying.

Is there any hope? Sorry if I confused everyone.

Thanks for any and all help!

David snipped-for-privacy@coosahs.net