If it can help,
I just encountered a similar problem approaching LIRN, freeware scenery by Napulevola.
Coming from PNZ, when overflying the airport to perform ILS Z, all the 2D panels and the menu bar disappeared.
All reappeared passing the airport and intercepting ILS and disappeared again 2 minutes before landing.
Is it clear that it happens when the airport in in sight, into the main window.
After landing I also cannot see any building, only runway and some taxyway.
If you or LM can find some common elements between Geneva and Capodichino maybe it can help to understand the problem.
It can be a Prepar3dv2 problem or maybe the two airports have some common features not compatible with P3Dv2.
Hope this "discovery" can be useful.