david_prentice:
I presume that the TFT will be plugged into row c of the breadboard.
Yes, b or c
Surely you would implement a voltage divider by dividing the voltage.
You are simply providing a 1k8 load to the Nano 5V logic. And a 1k2 resistor in series to the TFT.This would probably work but is not ideal. (A series resistor limits the current going to the TFT substrate diodes)
Yes, you're right: I switched the TFT and 5V nano pins! 
You should connect the Touch SCK, MOSI, MISO lines to the bus.
What do you mean 'to the bus'?
To make a voltage divider: move the 1k8 resistors to row a and GND.
David.
I'll do this when I'm back home. Thanks again for your help.
One more question: should I use the CS pin form the touch (labeled T_CS) or the CS from the display (label CS)? Now, I'm using the latter, and just aiming at testing the touch with the code provided by 6v6gt.