Windows USB integration with R4.1

I am having several problems with usb integration in qubes 4.1. I initially wrote in another post in a somewhat rambling manner, apologies can you delete, not having found this post immediately. I am trying to write the issue more clearly now.

I installed a fresh version of Windows LTSC as a Standalone VM after upgrading to qubes 4.1 from 4.0. In the previous version, the VM was working perfectly.

I followed the tutorial to install @jevank qubes-windows-tools-cross, which I also installed in dom0, and I had also already installed the package xen-hvm-stubdom-linux-full. I also installed the xenbus and xenvbd drivers as suggested in another guide.
My qvm-features output is

stubdom-qrexec 1
rpc-clipboard 1
os Windows
audio-model ich6

The audio works quite well and the VM starts up without any problems, suggesting that the gui features have been taken well. However, when I try to copy any files from another vm the output is:
Filed to execute qubes.Filecopy (From nameVM to namewindowsVM).

The content of the policy is $anyvm $anyvm ask. Modifications to it have not produced any results.
What could this be about? Should I perhaps modify the new 5.0 policy in some way? However, I still don’t quite understand how to do this. Should I install additional drivers? Could it be something to do with how I created the VM?
Any help is appreciated, thanks in advance.