The other issue I had was the inner siding and points combination. This combined with changing heights caused all sorts of problems with the locos - bad connections, derailments etc. It basically meant the siding was useless.
I removed all the track and cork from the board and then removed the board entirely, replacing it with a equal sized piece of 9mm MDF.
I then laid a single piece of cork sheet, with extra height on beach side as the attached extension board on that side is a millimetre or so higher.
The outer loop and siding was relaid as before. However the inner loop has undergone a transformation. The inner siding is now a complete loop, and the complication siding junction as gone and the siding feeds directly into the 3rd platform at the town side station from a a new curved point from the other side of the fiddle yard.
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Whilst the outer loops are all radius two or great I have had to compromise with the inner most loop, using radius one curves. As the original inner siding was also radius one I don't see this as backward step, although its not necessarily a satisfactory solution either. But given the space it really is the only solution!
All the wiring has been redone (mostly reused, I only had to solder one more wire!) and connected, and the next step is to test the circuit and the locos for reliability.
New track plan...
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