CAPPilot posted:For some reason my RR-Track software will not connect any track to the fast track O-72 wye piece, so this is a best guess.
You have to use the 120xx make up piece on each outlet of the wye. They are on the turnout menu just below the wye selection. I think there are a couple of other Fastrack turnouts that also require these pieces. I believe these are the pieces included with select turnouts. I started out to use Fastrack a few years ago, but went with Atlas instead and I have forgotten a few things...