Hey that sounds good; I used to work the same way with an older car sim: I was making the models with Max, then exporting them as 3ds files to a dedicated converting program and then to the game itself. The problem was that 3ds format breaks vertices on the limits of each texture mapping zone, thus creating sharp angles in some undesired areas.
But I would need to make familiar with particular CFS3 requirements in terms of modelling anyway.
D'you have any CFS3 aircraft model in a file format I could load into Max so I can see how it was made (polycount, texture arrangements, moving or detachable parts, texture application type, part axis location and things like that) ?
Typically, Max can read many formats like 3ds, obj, dxf, VRML (wrl), lwo etc.
I know those pics are totally out of topic but this is the kind of models I make for video games. The JPS Lotus textures were painted by a belgian graphic artist from the CREW development team.