Hate to turn you down on this fabulous opportunity,
@jksmurf... but I think I'll pass on it and let someone else tackle this one?

Not too familiar with Tailscale either... how are you using it? Just general remote access to get to your internal devices behind the router?
No problem Viktor I can imagine what might look simple to me or others ends up being a world of hurt for a coder as requests and glitches mount, so I totally respect your very polite response declining my request

.
I used to use Wireguard for direct connections as Asus/Merlin’s implementation was pretty simple and iOS and Win Notebook devices could all connect quite simply and securely once set up.
However I got an ISP (who I will change eventually when the Contract expires) who offers internet only behind CGNAT, which WG doesn’t work through. This was for a holiday place about 9000kms away, for remote access to the Router, to check various IoT devices were working, turn off and on Hot Water and just generally checking if the internet was working and TBH, satisfy my inner geek. I had a static IP address for a while to get around this.
Anyway enter Tailscale with an RPi3 (also to be replaced, maybe by a direct implementation) as a subnet router, to get around CGNAT by ‘advertising’ a route. Having used Tailscale I just found it convenient to set up on various devices and you can see which devices are connected, join the Tailnet etc.
I was using an RPi4 at home (then AppleTV) as a subnet Router but I liked the idea of Tailscale on the Router (my GLiNet Beryl AX does it, but it’s a Travel Router). So this brought me to that thread in which
@RandomUser777 cleverly found a way to make it work. For what I want to do (access a remote Router), it was just a nice thing to have it integrated into the Router as opposed to a separate device. I have no idea if this means it is slower or faster due to the limited CPU power.
So that’s the story

(sorry for hijacking your thread btw).