It would appear that moving a turntable after you've laid it down and attached tracks to it is a fatal mistake, as far as the route is concerned. Unless there is a way to either a) snap the turntable to the existing tracks or b) fine-tune the rotation so that the new turntable is in exactly the same position as the old one, it seems I now find myself with no option but to delete the turntable and re-lay ALL of the track it leads to, up to and including the sheds / buffers. Re-laying only the "stubs" leading off the table is useless, since they won't line up with the rest of the track that's been laid down. Any advice would be much appreciated.
This is my track layout. Although it can't be seen in the shot, all the lines leading to the turntable show as connected, i.e the red rectangles are gone. I have yet to lower the ground around the pit, that can wait.

I drive onto the table and whoops, wheels go straight through the deck and onto what I presume is the "real" deck, i.e where the sim thinks it is. The loco is not derailed though and can still be controlled at this stage. However stopping on the turntable and hitting G or Shift+G does absolutely nothing.

Drive off the other end of the table, and back onto the track we go. A couple of inches further though and the loco derails, clearly sensing something is amiss.

A puzzled JB.
