RUNDOS1 is a small utility developed by sd_snatcher. It enables you to run MSX-DOS v1.x on top of MSX-DOS v2.x. As weird as it sounds, doing this allows you to run a lot more games, since it will free quite a bunch of RAM for memory hungry games.
It solves the problem of running the Playball III - Enhanced HD version over MSX-DOS v2.3x, but can also be used with any other game or even to try to workaround compatibility problems with the MSX-DOS2. The included text file has instructions on how to install and use this tool.
Relevant link: RUNDOS1
