WhiteTower: Here is something I don't think you will hear me say often, but I believe Fencer's second answer is wrong. (not really wrong, but not the correct answer.)

The first question/request was about putting a green dot on the game page themselves to see if a user is online.

The answer to this is that if the user's "doing" is under their name, they are on-line. If nothing is there, then they are not on-line. No need for a greed dot also.

The second question/comment was that it did not work if someone was cloaked.

The answer to this should be that it does work when someone is cloaked. If a cloaked user is on-line, you will see the "user is cloaked" message instead of they are doing. If they are not online, then you will see nothing.
... and if you are the cloaked user, you will see a message saying "- disabled when you are cloaked -" if someone else is on-line. Again, blank if they are not online.