Here's the REW link
http://www.hometheatershack.com/roomeq/It is very powerful, but pretty easy to use. What are ECT tests?
Maybe just twisting it by 10 degrees, move the right speaker out into the room 6 inches, and move your chair to the left a couple feet. That will get your right ear away from the right wall, if after a while you start to "feel" it there.
Another thing I just noticed, is the two small parallel facing walls just behind the speakers. They will make a slap echo that will ring very long. They are a small surface, but they are right close to the speakers so the signal will be strong. And the nook may amplify it toward you. If your floor tiles are 1 foot, then those walls are 9.5' apart and the echo frequency will be 1425Hz, upper midrange, ears are very sensitive to that. But it's high enough freq that 1" panel or some soft art will kill it. By the looks of your neat decorated room, there is likely a wife lurking, she can find some cool tapestry wall arts for you!