I too am interested in a server 2012 R2 vm. The problem I've ran across is that it never finds the hard drive to install windows on, even after supplying the virtio drivers. Anyone ran into this issue with server 2012 R2?
I may check that out. I was able to get into the docker terminal, but then got an error that calibredb wasn't a known command. I've been using calibre on windows, to convert books to mobi, then using dropbox to send them to my kindle. I was hoping to automate adding books to calibre and then a nice web interface to send them to my tablet, kindle, etc.