TOPIC:

I have used this feature, it works great for individual files. But it doesn't seem to work with local files when working in a team. I left it as default for 5 minutes but the .OS file didn't change anything.

You misunderstood the service description. Read it more carefully: the service calls the "Save" command on a timer. The .oc$ file is created once when opened and changes when using the "Save As" command. This file is needed to be able to roll back to the original version.

I completely understand how it works, when working on an independent file, each time it is automatically saved, the time parameters change at the time of saving. Worksharing files also create .oc$ files, but they do not automatically save according to the set time. If you save manually, the parameters of the .oc$ file will change.

The code doesn't differentiate between workshared and not-workshared files - the service will call the "Save" command for everyone. However, it won't call the "Sync" command.
Also keep in mind that the service counts down the time from the document's last modification. If you simply open the file and wait for the timer to save, you won't get it. You'll need to make some changes to the file.