You're welcome. :)

If anyone is curious, the results are like this:
http://www.youtube.com/watch?v=Ui-gSaI_du0

I still consider this halfway done though... Why?

I can't figure out getting wheels to roll properly while following the path. It doesn't matter if wheels have no visible texture or smooth geometry like in the linked example, but it would matter if you had wheels with texture or bits of stuff attached like drive wheels on a steam engine. Rigid body physics behaves a little wonky with constraints (at least I'm not having luck), and I'm nowhere up to speed on driver or Python scripted animation. I know part of it involves knowing the wheel diameter (easy enough via correct object dimension) to get circumference (using some circle math involving pi) and then path length in units (count 1 unit boxes arrayed to fit path to get close) to figure out number of rotations (path length divided by circumference), but the exact details is where I get lost. (Getting Blender to do all that for you. I sorta know what has to be done, unfortunately just not Python and/or drivers part.)

If only I it were possible to port the Sparrowhawke3D wheels modifier Carrara plugin to Blender. (It's not, but something equivalent would make life easy.)

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Barbequed Pixels?

Your friendly neighborhood Wings3D nut.
Also feel free to browse my freebies at ShareCG.
There might be something worth downloading.