1) Knees together, pull your opponents arm in the direction opposite their thumb (preferably keep the thumb up), keep your butt close to their shoulder, elevate your hips. (there's probably more) 2) If you are facing south at the beginning of the throw, an Ogoshi throw is in about the E-NE direction if you are fighting in a right handed position (left hand initiating the pull, right hand on the opponent's back). You are throwing the opponent over your back more to the side than forward. 3) Never used any leglocks (I'm primarily a Judo guy) but I'm going to guess that it's an ankle lock. 4) The ankle is a very fragile joint with a lot of tendons and bones that can be broken very quickly. A heelhook can do tremendous damage very quickly unless your opponent knows how to counteract it. An inexperienced training partner not only won't know where to move to relieve pressure, but they may panic and move in a direction that increases the damage. EDIT: I re-enabled messaging. Great topic.