Ok, so the problem is back. High idle, coughing exhaust. After being completely reset, everything is fine. Then around 600 miles later the idle starts fluctuating, then it starts idling high and hanging at 3k RPM for a while before settling back down to 2k RPM. And the exhaust 'cough' is back.
Here's a video of the chuffing exhaust.
https://flic.kr/p/nAG7tu
One thing is now certain: I will not be going around the world on THIS bike. Very bummed.
Good thing I got that extended warranty. But back to square one.