After thinking my BTB file was broken / gone forever, my Track 64 project is back on! I decided to go straight into building the circuit for rFactor, and skip all the usual details I put in using Sketchup.
Taking inspiration from random junk, this circuit is based on a small piece of wire I saw lying around on a rainy day. After trying two designs, I settled on one and Sketchup'd the basic layout.
Unfortunately the spiral at the end of the back straight didn't work out, with yellow flags displaying and invalidated laps every time I drove through the tunnel, so I tweaked the design to add I nice open hairpin, a great overtaking opportunity.
There's a youtube link below of a little test race I did, apologies for camera phone quality. It's WIP, plenty of scenery and adjustments still to be completed.
https://youtu.be/MqwAlAQmGGg
I believe the circuit is around 4km long with a laptime of around 1:25 - 1:30 in a GT car.