2013 Enclave engine light on and burning smell

I tow a 2015 Acadia and you did all the right things as long as you did them in the correct order per the owners manual.

The check engine lights comes on after towing on my car too, sometimes. After driving it several times afterwards it goes out. I have not had any engine problems

The smell could be just oily build up on the cars exhaust system from the diesel exhaust from your motorhome. I have never experienced this issue. Did you release the brake completely once hooked to the motorhome?

Paul