To run wutherobots.wlua, you'll need:
On Windows, you can get all this and more by installing Lua for Windows.
Outside of Windows, check your local package manager (which will most likely have packages for Lua) and/or Sourceforge (there are some good tips out there for setting up the files you can get from Sourceforge if you search for them).
Both robots execute the procedure in proc.txt. All 5 possible commands are shown in the sample procedure (SWITCH performs a GOTO if and only if the robot is standing on the switch at the 0 position). The goal is to bring both robots to the same position, at which point the window will close. (A solution can be found in spoilers/solutionproc.txt.)