I don't blame the Houston fans for whining over the officiating...that's a time-honored fan's right and we've certainly done our share around here. The new policy of the NBA of acknowledging bad calls on just certain plays does nothing but feed this dynamic of "the stupid officials cost us the game". The reality is that we all know that there are blown calls both ways every single game. Howard wouldn't have even been in the game for the "bad call" if Salvatore hadn't had his head up his butt when Dwight threw the elbow into Rolo's chest just minutes earlier.
All of that said, the OP is right. Houston lost this game because they simply didn't take care of business when they had the double-digit lead with less than 5 minutes to play. Howard's ineptitude at the FT line cost them big and Harden couldn't hit the big shots. Hopefully, all of that continues tonight.