Regardless of when registration ends, I plan to post the Rules for Survivor IV, as well as a general FAQ, as a "sticky" in the OT forum, sometime around March 5 or 6th. The game will not officially kick off, however, until March 7. That's the day that you'll really need to check in if you are slated to play.
Generally, each round will last at least 24 hours. Rarely (and almost never until we get down to the final few rounds) it may go faster. But you will almost always have a full 24 hours to lodge your vote. So even if you can't make it to the forum, for some reason, on March 7, you could probably still get in your shots on the morning of March 8.