Even if I'm an old very P3D and ORBX fan, I discovered PTA recently.
Is a nice software no doubt about that.
I tweak two things in particular in P3DV4, haze quantity and color, and the intensity of any casted shadow on terrain.
But recently those shadows have totally disappeared, no more casted cloud shadows, no terrain shadows, no casted building and trees shadows.
I still have the cockpit shadows anyway.
Needless to say that all shadows are activated in the sim.
Mainly I tweaked the object diffuse sunlight ratio :0,88
and the terrain ambient sunlight ratio : 0,90
Cloud shadows depth is 1
I tried to delete the shader folder but it didn't help.