C03 is old software. R03B is the latest and was a complete re-design of the software as well as hardware upgrades including a new more powerful microprocessor back in August of 2008. R03B also has enhanced tests that can be run from the main menu. I can send the software manual by email if anyone is interested in more details. All the older RAM or Modelbau ECU's can be upgraded to the latest hardware and R03B software.