Doors CS 5.1, the completely bug-free version of the popular shell and GUI for TI-83, TI-83+, TI-83+SE, TI-84+, and TI-84+SE graphing calculators, has officially been released today. This version fixes five bugs that were found by members of the community in v5.0, the worst of which made certain large Ion programs unceremoniously crash. There was also a bug in the program count routine that had never been completely fixed, and several Properties tools were optimized. You can download it below; enjoy! The next major release will probably be Doors CS 6 and may not be available for at least several months.