We are building a 20' x 34' in ground pool with concrete walls, vinyl liner & auto cover. The cover company came today and installed the track. I had to leave for awhile and when I came back they informed me that the concrete walls were not straight. They bowed out in the middle about an 1.5". I call the PB and he said he never had a problem like that before and the .25" foam under the liner will cover it. That doesn't sound right to me. If the track is over hanging the walls in the middle .75" on each side then there will be a .5" space between the foam & liner. Also this will be up out of the water by the top of the pool. The tech from the cover co. said the PB should flash cover the walls to fill in the gaps. I'm worried if that concrete or cement will adhere to the existing walls. If the PB won't fill in the gaps I was thinking of having him sign a guarantee in case the liner rips. I was also thinking of calling the liner company for their opinion. What do guys think?