You have guide how to build and install QWT on @jevank github: GitHub - tabit-pro/qubes-windows-tools-cross: Qubes Windows Tools build with mingw, wine and qubes-builder
Before that, You have to install Windows in HVM. It is really straightforward. Yo have to create Qube as standalone not based on any template. Check “Launch settings after creation” and in the settings give the Qube 50GB of System storage space. In Advanced, uncheck (if checked) “include in memory balancing” and give qube 4096 MB of RAM. Then switch kernell to none, and finally run from ISO located in some other qube downloaded from MS website. Then installation is like on normal machine. You only have to be sure that You installing it on System partition (first on list).
After installing You can install QWT using installer from attached ISO (instruction how to attache on that github link)
Finally You can add some features flags to VM running commands in dom0:
$ qvm-features <YOUR_WIN_VM_NAME> gui 1 $ qvm-features <YOUR_WIN_VM_NAME> gui-emulated 1 $ qvm-features <YOUR_WIN_VM_NAME> qrexec 1 $ qvm-features <YOUR_WIN_VM_NAME> stubdom-qrexec 1 $ qvm-features <YOUR_WIN_VM_NAME> audio-model ich6
also there is a hint in some guides to increase qrexec timeout but I don’t know if it is still necessary.
$ qvm-prefs <YOUR_WIN_VM_NAME> qrexec_timeout 300