I'm pretty new to the three-rail "thing", after working with HO-gauge years ago. My problem is this... I've got a 4-switch MTH-brand layout, with 2 switches working fine. The other two, which join on the curved sides, seem to short out when activated, regardless of what I do. I've tried track power vs aux power, wired toggles and DCS. If I physically move the switches to other locations, they work, so I'm fairly sure it's something with the layout. I understand blocking and such on two-rail layouts, but I thought that three-rail was immune to that. I have attached a quick diagram with 4 switches indicated. Number 2 and number 4 are in conflict. Interestingly, if I disconnect the tract between them, the problem goes away and both switches work. Is there an approved way to insulate the two from each other, or is there a better way? Any help would be appreciated.