1) I said I may not be around during the rounds. Do not hold up the draft waiting for a trade to go through. Pick players for your trade partner and resubmit the trade with players in place.
2) If a pick was missed in the 1st two rounds, the commish will make a selection for them at the end of the round.
3) Teams don't have to (and in most cases shouldn't) wait past their time to make a pick because someone else made a mistake.