There is an object called a northmarker, that when placed in a cell, makes the compass North point along the direction of the Northmarker, if that's what your asking.
That is what I'm asking, thanks.
There is a button on the navmesh toolbar, if you hover over it it will say 'finalize' .
Yes I found that and pressed it but it didn't seem to do anything. Though I noticed the navmesh object in the Georgetown Origins cell had an asterisk beside it as if a change had been made.
You can also align your cell pieces by placing the very first one and making sure its rotation is set to 0 on all three axes. Then adding pieces to this one will ensure your whole cell is aligned along the north/south east/west lines.
That doesn't really apply to what I'm doing right now since I'm only using copies of existing homes. Specifically the ones in Greyditch and the one townhome in Georgetown. There's three townhomes in Greyditch facing north and one facing south. The one Georgetown faces east. Three of the Greyditch homes have identical layouts though so by using the north marker I now have 3 different floor plans to work with. Two are just reverse layouts though.