to get the speedometer display to work I needed a new function in
irrlicht. I've added this function for OpenGL, and the replacement files
are included in the latest SVN version (r3781). If you want to see the
speedometer, please follow the instructions in irrlicht_1.5_update/README.
I hope that the next irrlicht version will supply this function (or a
similar one) in its next release.
Note that STK should still compile even without a patched irrlicht
version, but it will not display the speedometer (and more elements will
be missing in the near future).