Security said that a permit was required if we were taking promotional photos, but I easily alluded to the fact that we were simply creative hotel patrons that were taking "personal photos," asking if there was a policy against such a thing. The guard, who couldn't see anything from the thin crack in the door, immediately was embarrassed at the notion that people might be taking private sex photos in the hotel, apologized and said he had no problem with such a thing, but that maybe we should not do it on the balcony. I apologized myself and said we'd try and be more discreet in the future.
This all comes down to my long standing rule of "It's easier to ask for forgiveness than permission."