In the Clocks you will want to look for some code that (IIRC) uses isHost() - that is how you allow different rights for the GM to interact/use the tool.
As you will be doing this on the CharSheet which is a node the player owns they will be able to manipulate the track (which is what you want).
If changing the track value should be kept secret then nothing else needs doing.
If changes should be broadcast to everyone have a look at HeroPoints or SpellPoints and see how they write to the ChatWindow -or- look at the Party Sheet and add another Tab there and each player would have a track there and all players tracks would be on the same page for everyone to see.

