Molasses is another great one for keeping bacteria and fungus alive in the soil, it feeds em and adds trace elements, which in turn feed the plants. AFAIK biobizz biogrow is essentially just molasses, but it's pressed from sugar beets rather than sugar cane.
Yep ya can use it throughout the grow. I usually water seedlings with it, dust the rootball when they're being transplanted, and then add some more every 2nd or 3rd watering.
It's the hardest part I reckon, probably cause its so overlooked when ya start off. I dry in paper bags in my tent, gets a mix of day and night temps that way and sorta kick starts the curing process. I've heard great stuff about those boveda packs tho!