I think the ‘withdraw’ option if you look at it in a time frame perspective goes like this:

When subs withdraw, they do it while the battle continues. So when they don’t get to withdraw at the end of the battle, it’s not like they ‘sat around’ afterwards for a while doing nothing… they were actually fighting in the battle the whole time instead. But… if the battle continues, they use that time to slip away. If they slipped away AFTER the battle was over, it would illegally extend their movement, because they would be using a round of game time that doesn’t exist.

Make sense?

Which one should I buy and what is the difference in the 2? Is Iron Blitz a release to fix bugs and be a better game, or is it just and expansion to include ‘marines’ & ‘destroyers’ etc.?

Appearantly you can’t buy Iron Blitz anymore, but you can still get the original A&A just about anywhere fairly cheap.

Seems like I read somewhere that once a transport has unloaded “it’s movement turn is over and can no longer move”

I also read in an online chat interview with the creator of A&A that it was not his intention for transports to “unload to 2 different territories adjacent to the same sea zone”

I don’t know if this is implied in the actual rules or not, but it makes sense to me… how would a transport unload in europe, then move across the sea zone to Africa and unload there too in the same turn? Would be like taking 2 turns.