I have looked into this further, and what ever assignments I try I always get the same problem: when I deactivate the reversers, the motion of the plane suddenly changes from reverse to forward motion, even though the thrust is at idle. This seems to be an issue for PMDG (or maybe MSFS) - I will investigate further when I return from my holidays and report/raise a bug if necessary. This is the simple config I ended up with: [Buttons.PMDG737] ButtonRepeat=4,2 1=PB,8,C65966,1 -{THROTTLE1_