I seem to remember there was indeed once a very basic rendition of the Lithgow Zig Zag on the DLS, but I can't remember what it was listed as or who made it. I did a DLS search and only came up with this old 1.3 version route made by advance: KUID:102657:100046
Whether that is indeed the one I'm thinking of I have no idea though, as I haven't downloaded it yet. As it's old legacy content it might also have buggy content that will throw up errors as well so just be aware of this if you download it.