First, phase the transformers per the video I shared earlier, or through this instruction sheet: http://www.martye.com/TipsandTricks/TipsandTrick2.htm
To have the ZW control the track, take the A terminal and connect it to the center rail of the track. The Common U gets wired to the outside rails (this is all in addition to the phasing wire connected between the U posts of the ZW and KW). If you have a second loop/block of track, the D Terminal of the ZW gets connected to its center rail and the Common U gets connected to the outside rails.
Now that your trains are running, lets get some track side accessories going. Since you have common return wiring with phased transformers, you can opt to forego the contactors for insulated track sections. This is all outlined in this Lionel document here:
http://www.lionelcrossing.com/...onel_145_56_1958.pdf
Again, if this isn't clicking, it can be a great benefit to have someone local stop by and get you started.
