1. Recirculation and water fills come from the same place.
2. Difference between recirculation and fill: The pump is audible during recirculation; it throws the water to the back of the tub. Fills look wimpier by comparison. Recirculation occurs several times during the wash portion of the cycle (usually for 30-60 second at a time) and during the two rinses. It can add water and recirculate at the same time.
3. There's a slightly longer recirculation time in the Bulky cycle, as I recall. Honestly, I wash comforters and bulky items on the Normal or Heavy cycle to get a full-length, 1300 rpm final spin. No explosions, yet, LOL.
4. Tumble speed is the same as shown for all full cycles except Delicate, which has a slower tumble with longer pauses. The Prewash option also utilizes a slower tumble, as does the Oversudsing protocol.