Installing osm2xp scenery

Installing an osm2xp scenery is no different than others xplane scenery.
The only thing you have to take into account are exclusions.

Osm2Xp will need at least an exclusion on "Objects" so xplane defaut autogen won't be visible.
(Osm2xp buildings are using "Facades" btw).

So if you have another scenery of an airport on the same tile, there are chances that your airports objects won't be visible, as osm2xp scenery will exclude them.

As xplane loads sceneries by their name, you should name your osm2xp folder so your airports objects will be loaded first.