Can anyone help me with this "Thomas at the Timber Yard" fault

[Super]

I would try repositioning that half gear on the spring, put it back together and see what it does....what do you have to lose in trying it?

Or, lift up this gear, (picture below) spin the turntable into the start position where Terrance would enter, replace that gear put it back together and see what happens. If noting happens or the same thing as now then repeat the same steps but rotate the table so the other side is where Terrance enters.  I say this because the position of the sprung half gear in the picture looks to be in its start place...no tension on the spring. So my theory is that when the turn table turns it will put tension on the spring which would pull the table back to its start position once Terrance vacates the turntable.