Can bus, so totally digital.
A proxy alignment might be needed, so the body knows there's a different headunit.
Maybe try that if you haven't.
If he is using a chinese unit - canbus wont pick it up.
The adaptor simply converts the digital canbus to analogue.
You have to program the chinese headunit manually, there will be a method for it within its settings, you simply push each button and you map it to what you want it to do from a list of functions in the chinese headset.
It will be in the instructions or the settings menu if its in english.
A few people on here have done this and also done it on the stilo.
hth,
Dan.
If you go on the xtron site:
http://xtrons.co.uk/community/wp-content/uploads/2016/12/Steering-Wheel-Controls-and-Set-Up.pdf