Our carpet is on hold as we having some water still in the corner of the two East basement bedrooms. It ain't much. But, years ago we had a company dig a trench along much of that East wall to collect run-off and then pump the water out, so we aren't sure why we have any water there. They came out yesterday and he asked me to tear out some wall to see what's going on.
Last night after taking Esther to a birthday party at Chuck E. Cheese (a.k.a., Vegas for children) and then picking up Joshua after his basketball practice, I went after the wall in the SE corner.
I think I found the problem. The wood from a 2X4 was drenched, just above where it attached to 2X2 at a "T". They are there for drywall attachment. There was especially a long screw through the 2X4 into the cement, and I think it was a main conduit: the screw hole is right above a cracked knot, and that area was saturated. I think the water then drips down from the wood, which is past the drain edge against the wall, and it then slowing moves to the low point between the rooms.
As you can see, the wood is very rotten, and everything was damp days after our big rain storm.