Cloudflare Zero Trust for Business Central - Websocket connection to 'wss://servername/instance/csh?ackseqnb=-1'

Just signed up for a free Cloudflare account to get a feeling for WAF, zero trust tunnel etc, as we are looking to make our web based erp internet accessible, with an appropriate access controls, and paid for support once ive ensured it works. Unfortunately I have fallen at one of my first hurdles, my ERP doesnt load properly over the tunnel, and when i look at edge’s console, i can see a couple of errors, the first being:-

onprem.manifest.webmanifest:1 Manifest: Line: 1, column: 1, Syntax error.

And the one i believe is most relevant being:-

client.js?h=9A746F7D2005B7D9CD047B80706F6CAC0C3B1DB76DF26047BD292BFAA0521E91&_v=21.0.52534.52761:31 WebSocket connection to ‘wss://fqdnredacted/instancenameeredacted/csh?ackseqnb=-1’ failed:

I have checked the documentation regarding websockets and ensured that its enabled in networks, and it says “No additional configuration is required to send WebSockets traffic through Cloudflare. Cloudflare will immediately begin proxying your WebSockets through to your origin.”

Is this only when proxying traffic, and not using the zero trust tunnel, and if so, do i have to do additional configuration for the zero trust tunnel (i have it running on windows).

Any help would be appreciated.