Best to ask on Pixar’s RenderMan Discord server.
Otherwise, Non-Commercial version only supports current stuff, everything else is available w/ commercial license.
From their FAQ:
- Can I download previous version of Non-Commercial RenderMan?
No, Non-Commercial RenderMan downloads are updated to the latest available version in order to keep the research community up to date, simplify community support, and to ensure that tool developers have a consistent target platform. Access to previous versions of RenderMan is available to all commercial customers.
IME, this also stands for OS.