I have never had a problem with my TPMS valves. It should not matter which position the wheel is fitted.
My existing wheels are 19" and I recently bought a a set of 18" alloys taken from a Land Rover with existing TPMS valves, I fitted a new set of Winter M&S tyres, inflated to the correct pressure and went for a short drive and everything was working correctly.
As long as pressure is set at or above the recomended pressure the car should recognise the valve and it's position.
I have noticed that if not displaying correctly, over inflate by a few pounds, go for a short drive and then reduce the pressure to the correct level, everything should now be working properly.
It always works for me.
GS.