I launched back to FSX and the FSDT KJFK showed normal jetways as they should. But, have DD KJFK in P3Dv4 with missing jetways. So, renamed KJFK_X.sdx.off back to original KJFK_X.sdx and the jetways came back to P3Dv4 DD KJFK. So, must be decided, FSX or P3Dv4 unless we keep same KJFK Developer airport for both sims; just guessing on this installing option.
That's your only option: decide which JFK you want to use, in both simulator.
Nothing to do with us, of course, since we are just getting duplicated jetways, created by something else.
The issue is the Drzewiecki JFK use SODE, and since the SODE configuration for that scenery is shared between the two sim, you are forced to choose the scenery, or disable SODE entirely in the sim, which is wrong, and of course will affect all other sceneries that use SODE.
Your best option would be just using FSDT JFK in both simulators, and the Drzewiecki airports for the other airport in N.Y., which is what most users do anyway.