Nice work so far.
Just a note on splines/lofting I fell foul of recently. If you use multiple profiles for the course for example, so you have a corner entry, corner apex, and corner exit profile, and you apply them as usual, the interpolation method is a smoothed type.
So if you drop the inside apex to add camber the profile is actually like a best fit in out in curve between each pair of points, rather than a smoothed profile between ALL points.
This means that you can end up with what is essentially a pinched dip on your apex, rather than a smooth blend to that new cross-section.
The linear interpolation is much better because it smooths out these changes linearly between the same point on the next profile. That isn't ideal either but it's better by a big margin for tracks.
The Max loft tool really is due an overhaul in my view. Axis management is really un-intuitive so you often loft a profile and it's twisted in it's long axis (so hard to spot till it's too late).
There is probably good process to follow if you work out what it is (like always draw left to right in top viewport maybe?! or always reset x-form and set axis coords per object before any lofting begins, I've even had EACH vert in a loft path have it's own local axis haha!)
I'm using 2010 and I'm sure the loft is still not very nice in 2011, maybe it's better in 2013 but probably not
You can obviously avoid all these issues if you just loft to get the basic shape then start to dig in manually but then you really want to be sure the main shape is right to start with because changing it later gets harder.
There are tools like smoothEdges by mariussilaghi.com which can help, you select a bunch of edges then press a button and a control curve is drawn to fit the edges which is then selected and you can control a whole curve with just a few control points. That is useful but again is fairly limited because if you have multiple track profiles (ie, lengthways edge strips) you start needing to select EACH one and then you are back to what feels like pulling verts rather than having a nice smooth control for the entire thing.
I know this sounds silly, and I haven't tried it yet. I used patch grids loads back in the old days but kinda abandoned them. I've recently been modelling a high density model again and they just work so nicely. Not without their problems but they do generally work and give intuitive results. WYSIWYG.
I'm very tempted to try them on a new track.
Ooooorrr, I'd try look into some other program for lofting. I'm not sure how good Blender is for example.
Max's lofting is really shoddy basically, imo. If it created a patch grid network from your inputs it'd be great, then when you edited profiles or corners the reference profiles and base spline were back updated etc, so it was a really intuitive to tweak but non-destructive process I'd be happy!
The limited interpolation is also a bit crappy too, with linear working ok but not being ideal for a WHOLE track as there will be bits where you want the other type of interpolation (no way to mix them)
Part of me thinks sometimes trying a sub-d track would be interesting, but then a big issue with that is that we can't set points to be intersected, they simply add a weight to the direction of our line, so you end up moving one thing for something else that was set to move off line. Grrrr (another thing I want to know the fix to, if there is one) Nurms work like that if you want em to.
Ultimately there doesn't seem any nice ways to build tracks in Max that give you the power to have a load of control but also be easily able to leverage the initial track profile spline path and cross-sections to make changes late on in the process.
At some point you have to dig in and at that point you want to be sure stuff is pretty damn accurate already to minimise adjustments later. It's possible just a royal pain in the ass to manage the loft once it's lofted basically.
I'd be tempted to look at loft solutions in other apps too, or maybe even better loft plugins for Max... hmmm...
Max is still good, just my 2p on it. Every track I make I fight with the bloody loft tool. I fought with it back in 1997, I still fight with it today
Dave