Considering the gas smell--- I think there's a strong case he's running too rich.
I would do as Bone Crusher recommended and take modes 2-3-4 down to .5 and see how it runs--- gradually increase them and see what happens.
When mine would cut out it was VERY noticeable and I would get a strong gas smell... so yes I think I was running too rich. Changing settings 5 and 6 took care of it.