Thanks, a lot, Galin. That's the kind of reply I was waiting for. I, too, came to the same conclusion(that the Noldor could visit, but not dwell in Valinor) but it was mostly guesswork on my part and I could not find any definitive answer in the texts.
But my first question remains unanswered(a definite answer, anyway). Were the Sindar and Silvan Elves(who were Teleri in origin) allowed to dwell in Aman alongside their Teleri brethren or were they holed up in Tol Eressea with those weird Noldor?