There is a delay. Asking springlobby to download the update always results in a 'file not available' for approx 24 hours after the new file is released (though it seems to be a lot longer lately).
FYI, there isn't a button that says 'download game' you just try and join, it tells you that you need to download the game and you select 'Yes'. Pretty simple to be honest, and worked fine until zklobby to replace all other lobbies gained steam and left Linux behind. So now a days we have a delay.
Oh I understand why Linux is ignored. AFAICT there are not many spring users who are on Linux, so it's not seen as important.
What is this rapid you speak of? something tied to zk lobby or is it independent?
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FYI: thanks figured it out. I must have installed rapid a while back and forgotten about it during that mess when zk was using older version of spring. I had to use pin zk:stable, not sure why but your command (in the other post) didn't work.
Cheers.