No it was Heathcliff turning off his immortal status, I noticed the mistake myself. It should of stated "Changing from immortal object", Or "Changing into Mortal Object", Or "Immortal off" or something else along those lines. I didn't really let it bug me though.
Over all though I really enjoyed the episode, Bye SAO will miss you!, but at the same time looking forward to the next arc
Edit: The best way to look at it though now, would be like what relentlessflame said. You'll have to look at "Change into immortal object" as like a check box on a GM menu an option of sorts. The red would indicate turning that option off.
He didn't do anything to Asuna at the time didn't think he would have to yet, she wasn't supposed to be able to move at all was under the Paralyzed status along with everyone else in the room except him and Kirito.