Robotics Studio, Tweaked Simulation Tutorial 2

Hi All,

In short, it puts two four-wheel drive robots on screen and makes them drive about by themselves.  Two differential drive robots go in as well, and a bunch of environment entities.  First time I've posted here, if it doesn't work, let me know.

It's a work in progress, comments / criticisms / tweaking welcome- post here, or email me at rdd@deakin.edu.au.  The code works on the September CTP. Note that I'm a newbie at C#, my experience is mostly with assembly languages on microprocessors, and it shows- I'm fully aware that the code could be better. 

I've taken the source code posted to the MSRS newsgroup for the pioneer 3DX robot, and made a few new classes and functions within the framework of Simulation Tutorial 2.

ThirdRobot : DifferentialDriveEntity
trivial variation of the code that gives you the Pioneer 3DX, with some bits turned off.

FWDEntity : VisualEntity
four-wheel drive robot class

FourthRobot : FWDEntity
Used to define the parameters for the specific robots "Rover" and "Fido" in this code

Robot Behaviour
a basic example of an if-else set-up to give wandering behaviour - I haven't got this working as a separate service yet, that's a challenge for next week some time, as is the tracked robot that I'm ultimately working towards.

Other Stuff
I wanted some objects for the robots to interact with, the code for the ball, stairs, ramp etc is all pretty simple.  If you start the dashboard up, you can still drive the Differential Drive Entity robots.

Command line to make it go, once you've copied the files over the ones in the existing Simulation Tutorial 2 location, is:
bin\dsshost /port:50000 /tcpport:50001 /manifest:"samples\config\SimulationTutorial2.manifest.xml"
Included in the zipped package is a screen shot, this is what it does on my machine.

The problems I'd most like to solve are:

1) If you knock the robots over, they won't drive around upside-down, and I'm not sure why not.

2) Sometimes the simulator crashes on launch.

3) It only displays in physics view- for some reason, the rendering gives the sky, but no solids.  It does, however, give the red LRF dots from the original Pioneer 3DX robot that I've left in.  Not really that important, but pretty pictures and videos improve my ability to get new hardware paid for around here.


Regards,
Ross.

PS - I'm having difficulty signing in to the MSRS newsgroup, some sort of Microsoft Passport Network problem.  If anyone reading this would like to post a link to it, there, it would be appreciated.