I've now done the ballasting. Even more grey. Everything still works although I did have a problem with one point it would not close, a little scraping and a blast with my small vacuum cleared it. Every thing seems to run well. It now needs painting, one reason for choosing grey ballast is that it gives you a greater range when colouring, the other reason is that I had most of a tub left from Kingsbridge Regis. the un ballasted bits will be where the concrete hard-standing will be. The grey part of the sleepers is from the dust of the ballast getting in the glue and on my smoothing finger. That will be taken care of when I colour the ballast, a mixture of browns and black.