Ok so first things first the big N never trademarked Orre.    Second things second Orre is connected to Kanto/Johto according to this map http://www.serebii.net/pokearth/  which is pretty much canon.   Taking advantage of this and adding a bit of realism we could add routes in between the two on that massive land mass.  This is where some of the dungeons could be located possibly.  Or we could do things the boring way and implement yet another boat at verm/slate (most likely