I have a couple observations.
I guess you can see what I was talking about with respect to the level you set the receiver to take the test. It's a bit high.
I'm surprised about the low end extension you're showing. You seriously had that type of output down to 7Hz?
You do indeed have a null at 22Hz and a peak at about 25Hz. This is where REW would offer more accuracy. I doubt the equalizer can do much to a true null, but it can bring down a peak easily.
Big recommendation...... use REW - so much easier..
brucek