Hi @sfbp,
When I bought the MZ-RH1 the only digital upload possible was the files recorded by yourself with a mic. Others should be blocked for music rights. Yet, as HiMD disc is a storage unit, like any USB key, you can even put text or PowerPoint files on the disc. For that you do not need any software, just your Mac will recognise HiMD as an external USB key or CD-ROM.
Best,