Those who read Ian Dunn’s Byways of Steam 18: 'the railway from nowhere to nowhere': the Grafton to the Tweed Railway 1894-1932, published by Eveleigh Press NSW in 2002, would know about the proposed line from Killarney in Queensland to Legume just over the border in NSW and onwards to Grafton via Bonalbo. While I don’t have plans for that, this download does have plans for parts of the Casino Bonalbo Tenterfield line of which parts of the Casino section were built. Not all proposals went through Bonalbo.
Some other proposed lines in the Tenterfield Casino area are marked on the historical parish cadastrals obtainable from NSW Historical Land Records Viewer. Perhaps start at either Tenterfield Parish or Tabulam parish around a probably era and follow the marked surveys through the adjoining parish maps
Section 30 of the Grafton Casino working plans and section was unavailable and so I did a substitute page with the history and track plans for Mount Neville at 477 miles 41 chains (768.481km), which was a station on sheet 30.
Also note one of the plans correctly shows what was usually known as South Brisbane Interstate Station as using its then correct name of Brisbane as it was known and marked on NSWGR sourced plans in 1930 at the line opening. The image resolution is the best I have.
I will eventually add to these folders as more becomes available.