Yes Umberto, I suspected this kind of problem too but I don't have the problem of missing taxiway line exposed in the other thread. I checked for another scenery installed, I had old JFK from Simflyers but it was deactivated and nothing change after a complete removal...
The problems exposed in the second and third shot of KJFK in my previous post are finally not problems. After checking the real aerial view of KJFK all is fine. But as I said before the rendition of most taxiways look different from KORD and LSZH even if a similar technic has been used.
The problem of truncated shadow exposed in my 1st shot of KJFK is due to a small variation of altitude between texture and ground in your scenery. I found a solution.
Apply the flatten line (scenery.cfg) of the old Simflyers scenery to your scenery and it solves the shadow problem. Here's the line :
Flatten.0=13,N40 41.17,W73 48.39,N40 39.09,W73 43.84,N40 36.25,W73 46.09,N40 38.61,W73 51.22
Overflying the parkings, I found a missing taxiway line in front of gates 20 to 30 (terminal 4). It's a part of taxiway K.
Hope this help