Hi, 

I have bought and installed product stated in title for p3d v4, however for some reason when starting p3d v4 it asked if I wanted to activate it which I did, etc and loaded elevation was off so I quite opened ftx and ran elevation correction, yet after it finished running I wasn't able to neither enable or disable it for eggp. now every time I load p3d v4 I just get default scenery with a duplicate ontop not perfectly right. 

I had same issue.  I fixed this by doing two things.

ONE:  inside P3D library, make sure you move EGGP to the TOP of the library.

TWO:  Inside FTX click on vector and then click on the elevation correction tool and search and the make sure once done you click APPLY!  *very important* 

 

This under most cases resolves the issue, however if at this point you dont have the scenery back, this final step should correct the issue

THREE:  Inside FTX go to the section where you can change where the INSERTION POINTS are managed, and the top one i believe is LC, move this down to ensure its BELOW EGGP and then your all set.

 

😉

D