Apparently, no one else has had this problem. I found a quick fix for it. You have to place a sprite in place of the wall, with out deleting the actual wall, then what ever texture your using, you have to extract it to a bmp, then you must place it in the level. To save time (especially on LARGE levels) just hit Build, then click UPDATE ENTITIES, then click OK. this will add your new image to the level with out having to wait an hour or two to rebuild.