There was a longer line for butterbeer that day. There was one 15 minute downtime each day to resyncronize the clocks. Until a drive blew up in one of the rv's on the 3rd week, requiring the first official evac. Keeping in mind there were 30+ (48 within the 1st month) vehicles each with a Kuka that has the tightest error tolerance out there. If a single motor rotated 0.5° or the transporter moved 75mm out of where it should have been, the entire building shut down. 30000+ people rode that ride daily (including opening day), with hourly counts in the 2k range regularly... Then they pissed off their guy, and he quit a few months before Gringotts opened. He comes back to these forums from time to time to watch UC fall on their face with a big "I told you so" grin.
This "Hagride" is about as basic as they come technology-wise. UC deletes proper ride testing from their schedule because the trades take it all up by being late and those opening dates don't change. Intamin just capitalizes on UC's own stupidity