Tunnel with WebSockets over UI

My goal is to get Microsoft RemoteApp working through Cloudflare Tunnels. This basically just needs an open HTTPS port to work. In my old architecture, I have a HTTPS NAT to my RD Gateway Server and that is all that was needed for my users to connect from outside the network basically.

However, it does not work with Cloudflare. I can connect to my RemoteApp Website, but I can’t really use the RemoteApps because the connection terminates while connecting with an unknown network error. Can’t see anything in the Cloudflare log.

However, I have new hope. I want to try it via WebSocket. The following link shows that WebSocket is possible with Cloudflare Tunnels.
However, all the posts about WebSockets and Cloudflare that I’ve read, use Cloudflare tunnel without UI, but with the locally managed config.yml file.
I use the UI. There is no option to use type WS:// present when creating a public hostname in the tunnel.

Now I have 2 Questions:

  1. Can I somehow use WS:// when working with the UI?
  2. If not, can I tell my tunnel to be locally managed by the config.yml instead of the UI?