Well, we haven't said anything, because you aren't supposed to do anything: it should work right away without any modification.
The only thing that might potentially cause a problem, it's the AFCAD files, but the AFCAD that comes with CYVR already takes into consideration the Orbx sceneries and should exclude everything that needs to be excluded.
This means, as long as you keep CYVR on top of Orbx in the Scenery Library, everything should work right away.