Is there a real entrance to Shafran off Browns Ridge Rd., or are you just cutting through someone's yard?
There's a trail just up the hill from the brook in woods between a couple houses, runs on or along the former trolley line. Pretty sure it's CT water company land, posted in some spots but I've not had issues in 20 years and trail sees regular use (ie not overgrown). There is one side trail that connects to the orange loop at Shafran, a few others that do indeed head into private land and wind up in backyards. Happy to show it to you sometime.
No parking on Browns Bridge though, but using the main parking, one could exit there and create a loop with Shenipsit Lake Rd (dirt) or connect to the Shenipsit Trail headed N... (or S, which is the dirt road)