Is there a bug on that Teleportation Stone at the first keep? Both times I entered Cyrodiil it does not let me open the big map through it, I have to run at the nearest keep always to be able to teleport to the others. Any help?

Thank you so much for this very clear explanation, Kevin. I've been wondering how this works since I first subbed!..
I don't understand why simple game mechanics as this are not in the help section or why Zenimax relies entirely on players to do what should had been their jobs. The "Game Guide" section being just advertising crap without a single "how-to" clue is another symptom of how badly this website is designed. The ingame "Help" section is even worse, and that's if you're lucky enough as to speak English. I play in French and I can tell you, the French "help" makes absolutely no sense 90% of the time, without even mentioning the 6-year-old spelling, typos and grammar errors.
Have the Web Designers and Writers ever actually played this game before they released this online?