Ah, that’s another question 
The previous guide is a little outdated so the community is working on improving the instructions. See them here:
If you end up following them, and get stuck at any point, feel free to reply there mentioning the step in which you got stuck. Feedback on people following the guide is great for improving it and you also get to have your issue resolved.
So it looks like you’re just missing QWT (Qubes Windows Tools) to allow for the integration.
Also, not sure if USB support is working (haven’t checked).