I have been flying the 737 NGX all day today and having a great time. The only thing I can't seem to get to work is reverse thrust on landing. Most of what I have read says to use the F2 key, and I do that on the Airbus and it works OK. Doesn't seem to work on the 737. I reduce throttle to idle prior to touchdown, turn off A/T, but the reverser never comes on. I noticed in my key assignments for P3D, I don't have anything assigned to the F2 key. Is there supposed to be an assignment, and if so, what?  

Figured it out, somehow my F2 key assignment got deleted in the last 2 weeks.  ( reduce throttle quickly). All working now.