I haven't used this feature since we were having those caching issues during preview.
If I recall, ashley disabled cache via preview(downloads a new version every time), I don't know if this applies, or if he has since re-instated it.
And as far as live:
[quote:1cthzouo]If you're online and you load the game, the browser loads from disk instantly as before. However, as the game is running, it checks for an update in the background. If you've uploaded a new version, the browser downloads it and saves it to disk. Then, next time you load the game (this includes refreshing the page), the browser loads the new version. Until then, the user keeps playing the old version.
The user plays his cached version, at some point it picks up a new version and starts the download whilst user is playing old version. Then when finished, and browser is refreshed the new version is used.
The browser object actions would / should trigger whilst user is playing old version.