Jeff,
I think it's the track bending. These two photos show the permanent position of the house and track. You can see the slight bend in two of the stalls.
I have used a styrofoam hot wire cutter on the entire layout to lower track and to create a more realistic look. The roadbed on the Rokuhan is too high and needs to be more at ground level. I'll post some pictures of that modification some time. You can see some of the pink foam cuts in the attached pic's.?
