Found a solution last night, for an Espace. Thought i would give it a go and it worked.
Dont press any of the pedals.
Press and hold the top button on the end of the right stalk.
Put the card into the slot.
Press and hold the start button and keeping pressing the other button.
After a few seconds the mph should start flashing.
Aftera few more seconds it should change to kmh and keep flashing.
When it stops flashing you can let go of the buttons.
Do this all over again to change it back
That was almost right. I FOUND THAT BY HOLDING THE TOP BUTTON ON THE STALK IN, THEN INSERTING THE CARD IN THE SLOT, THE MPH STARTED TO FLASH. When it converted to kmph I dipped the clutch and THEN pressed the start button. This locked the setting to kmph rather than mph.
I was able to reverse the procedure by carrying it out again. Thanks for your help. You never know what these cars can do - tricky!