I have auto start/stop working perfectly, but it requires a Linux Host and a custom solution (see 3rd bullet point).
How is Autostart supposed to work for NT4 guest?
I started off building my Host as Windows 8.1 and it didn't take me too long to realise I'd have better control and more automation options if I went with a Linux server than with windows. Now I have my Linux Debian server working flawlessly and doing more than I could ever have imagined than had I stuck with windows. Just an idea.