Neat! Glad to hear
Yeah they’ve done a good job with their documentation.
I was tempted by it several times already to try some features I didn’t even consider using.

https://github.com/bpc-clone/bypass-paywalls-firefox-clean

Just update it to the latest

The first patched release is version 5.0.1, released 2 days ago.

Summer Eternal has Tuulik and Red Info has Rostov and Kurvitz

Yup.
Tailscale has some documentation about it, and also a bunch of examples (And apparently one specific to Immich).

Since you already got some replies, a bit of a different approach would be to set those services up using Docker and having Tailscale as a sidecar to each one of those.
You will then be able to access each one as a seperate device. immich.*.ts.net etc.

Kurvitz and Rostov have their own studio called Red Info.
Although I haven’t seen anything about what they’re working on.