I have it working in Windows 7. Ths system recognises the cradle without any problem. Th software is another question... I haven't found a way to drag and drop music to the DMS, always have to create .m3u playlists and import them.
Anyway, you should try with a Windows XP system, just to verify it works. An easy way is deploying Windows XP Mode: it's a completed licensed Windows XP running inside Virtual PC. Just look for it in Microsoft site. Once installed you can start the WXP machine and connect the cradle to it. Anyway, if your W7 system doesn't recognise the DMS partitions you can't connect them to XP...