you may want to read through this thread for some tips on that
quick answer, not on the stay itself but on incidentals that are applied to your bill.
I don't think so Tommo781. I think you will get points for the upgrades which is technically 5 nights worth but you still wouldn't get points for the actual stay from what I have ever read in the rule book. One of our teammates should probably chime in here...jmart, The specified item was not found., ansaa?
I Can't imagine you'll get any nights credit as the stay is paid in points, the upgrade is an incidental charge for which you will get points, as long as you're staying at a FS.
It seems that nights credit for points stays is coming in though. I think Starwood already does it and IHG has just started counting redemption nights towards status. It's not reached Marriott yet though. I'm not sure it ever will.
The only way to earn Elite Night Credits via using points is if you cashed points in for Marriott Gift Cards or use the Instant Redmemption option. Most likely both options would require you to use a higher level of points to cover your stay versus using the points for Room Redemption.