Now I'm wondering, why would you ever use connectors when you can just use the standard atomicity tricks ( adaptors or hashlocks). Naively it seems like a worse choice, am I missing something?
Ruben's old gist was extremely helpful at least for the basic mechanism:
https://gist.github.com/RubenSomsen/a394beb1dea9e47e981216768e007454
Discussion
The UTXO you are trying to swap for doesn't yet exist.
How would that work?
I think I got it, though it took a while ... for the relationship between forfeit transaction F and round transaction R, you want a *unilateral* constraint. That is, the server can get F only if R; and Alice (the participant from previous round) doesn't need to play a role in that round creation process (well apart from actually providing an F of course).
To have it work the "atomic swap" way it would have to be the counterparty (Alice) that was broadcasting the R, unlocking a secret for F. But that's not how this works, the action is all controlled by the Server.
Especially because there is more than one Alice :)