Look, if you sight down the nose of the cushions, and you have ball hopp in some areas but not others, and the cushions are mounted flush to the top of the sub-rails, you have to be able to see the low spots in the nose of the cushions by looking straight down the nose. If the cushions are flush to the top of the sub-rails, and there's areas in the cushions that are at the correct height, and areas that are low...causing ball hopp, then the face of the sub-rails had to have been passed over on a table saw. The reason I say this is because if the person using a table saw isn't very careful with this process, then you can have a twisting effect of the rails passing by the saw blade, not to the point that it's removing the top side of the bevel, but in fact the lower side, which would cause the cushions to dip a little in that re-saw area, so that when the cushions are re-glued to the sub-rail, you have dips in the nose of the cushions. Now, correct me if I'm not understanding what is going on here. Was the cushions replaced again on the set of rails you have now, or are we talking about new rails here with factory cushions mounted on them...because I don't understand what's going on here....it's not that hard to find out why a ball hopps off the rails

The reason I asked you how wide the cushion was from the nose to the formica of the rails is because that would tell me if some of the wood was removed or not from the sub-rails, but would not tell me if only a slight amount of wood was removed, like just enough to clean up the glue, but even in re-sawing the rails to remove the glue could create the problem of cutting to deep at the bottom of the sub-rail creating a change in the bevel of the sub-rail where the cushions mount, giving you that dip in the cushions
Glen