it's not parametric, but a little trick i use to see the grid in my 3D window:
save your building's 2D grid (just the grid - nothing else) as a DWG file and then open that same DWG file as an object (File>GDL Objects>Open Object... and navigate to that DWG file).
save the object into your library and then place on each story of your plan.
you need to fiddle a wee bit with the 2D representation of the object so that you can place a couple of hotspots by which to accurately place your gird object . . . but that's it: it shows in the 3D window.
and normally the grid doesn't move much once design development is well under way, so updating is never too big a deal. it would be nice to have a 3D grid to snap to though. or was that what you were after originally? my object grid is really just a visual aid . . .
~/archiben
b e n f r o s t
b f [a t ] p l a n b a r c h i t e c t u r e [d o t] n z
archicad | sketchup! | coffeecup