I used to have one of these rail movers.. its exactly the same.. I guess you mean new to you? I had one about 15 years ago.. but it did not hesitate at the ends, now they give a moment on each end which is a lot better...
got my ducting figured out...funny, sucking works very well for movers. blowing was forcing the inflated duct to be forced into things, whereas the sucking makes the ducting shrink when the mover is close to the vent... im trying to reliminate the need for a/c in this vegroom by using extractorfans and properly ducting the light.