Dear Nick,
Iìm very sorry about this very late answer, but I had a lot of problems with my work (and in my life), so I had no time for flying with the sim. Now it's better and I've done the try you asked me. Without Taburet EU Dem 4 airport is ok. I don't know if there is a way to keep airport and Taburet Dem without having the elevation issue.
Thank you
Luca