At the moment I'm using all my add-ons sceneries (also Orbx) and other tools (like GSX, AIG, RAAS, etc) simply copying the scenery.cfg and addon.xml files into V6 folders. Everything seems going well, but for sure I have to check more (for example also the effects are taken from V5 and do not need to be copied in V6?)
I have used the regedit trick to finally see PMDG aircrafts properly running in V6 (consider that before you have to uninstall them from V5).