To add to this, you can see how many of the Adagio Lanpak licenses are in use from the Help | About screen. If you have a 5-seat Lanpak installed and 2 of the licenses are in use, you will see '2 of 5' displayed here.
Because of our Lanpak licensing model, this won't provide an accurate count of the number of users in Adagio, nor who is using which program. Without a System Manager, this is a little more difficult in Adagio.
If you ever attempt a process in Adagio and are prevented from doing so, typically the message will indicate which user is locking the process.