Set up this site
This happens once. Type the set-up key you were given when the site was created, and your email. You will be given a long sign-in key to keep in your password manager.
Save this sign-in key now
Put it in a password manager. It is shown only this once: if it is lost, another admin can make a new one.
Sign in
Venues
Each venue's copy of the show checks in here by itself. Switch a venue off and its copy locks the next time it is on the standby screen; it never locks in the middle of a show.
Updates
To publish: run the update tool on your computer, then choose the two files it made (they are in dist/update). Venues pick the update up by themselves the next time their app starts.