I can not recommend this scenery highly enough. It is very good, especially, if you couple it with Ortho4Xp and Simheaven X-Europe 5.5. It is just so so good and would truly deserve to get its own review.
As for the installation, when dealing with .exe installers: I can only recommend to create an empty folder and copy the Xplane11.exe into it. Point the installer to that folder, instead of your main sim-folder. Afterwards inspect the files that were dropped and manually copy them to your sims folder.
I did so with EDDW and did not encounter any of the errors and debugging you described here.