FWA505 setup / troubles

hi, I got this one, as my basic research said I could rate limit the wifi part of it, using per SSID rate limiting, via Nebula. Maybe it was Gemini AI who tricked me IDK.

Lot's of Nebula stickers and QR codes etc on the box and router.

My findings:
1. The web interface, while nice, does not have the rate limit feature.

2. I tried following the quick start guide, it says to install Zyxxel Air app, but when I follow instructions it says "Product not supported." ?!?!?! What is this?
Not sure the app would support rate limit anyways though.
Funnily I found this Youtube video claiming it is working:

https://youtu.be/T_EJUWo-2ak?si=g10f2X9cibj_OECB

3. I tried the Nebula approach, which yes did not feel very consumer oriented, but eventually I got it in to an account and site.
But then I found it it can only be "lightly" managed via Nebula, no configuration, like set up of WIFI, SSIDs etc is working from there. Spent an hour on that :) I added SSIDs there but it had no effect on the wireles router. And yes within there is a rate limit per SSID function, but since its not configurable from there it has zero effect of course.

So I'm super confused about it all. The Air app, support or not. And does it even matter, can this or any other Zyxel indoor 5G router support rate limit at all? If only the local web UI had it…

I want to limit my cabin smart tv to use all bandwith it can when using streaming apps etc, it will go to 4K easily and the monthly GB quota is gone quicky. So I need to limit it…