I've started recreating a Vekoma Flying Dutchman style roller coaster (X-FLight/Nighthawk/Batwing/Firehawk). Using the node coordinates from the No Limits track which was actually supplied by Vekoma, I have created points and splined them together. I have 65 points already and I am only through the first couple of elements! The spine is much more smooth than the Loch Ness Monster model as there are many more node points.
Everything besides the node points is all custom made by me including the guessing on what the actual dimensions are.
Maybe tomorrow I will be able to figure out how best to do the rails as that is still proving difficult. Doesn't help that CATIA has been living up to its name: Crash And Try It Again.