See the links I just posted. There's a couple of mile break (6?) in the Rock Island Spur Trail. I have no idea if this is recent, or what. We followed the RideWithGPS info, and it worked out for us super-fine.
....(unlike the campground in St. Charles...... the Barnhouse-Riverview thing... with the NO TRESPASSING sign at the end of the drive - sheesh. )
Interesting, how far west of Windsor did you lose the trail ?