I can’t remember anything significant. Probably just bug fixes. Roland would always document new features if added to an OS, but were often less clear about what possible bugs they may have addressed in a minor update.

On the whole, major new features warranted either a whole new version (v.1.0, v.2.0 etc) and major bufixes got a decimal upgrade (v2.1, v2.2 etc), but usually second decimal updates (v2.02, v2.03 etc) were minor bug fixes that perhaps only addressed one bug.