No. Once your map has been approved, you can update it as much as you like but it will stay approved don't worry. The only thing that will happen is that your map will be at the top of the list. Just don't exaggerate with that, still update only when required.
Come on! I see people who really desire to play your map so I can imagine that other people will enjoy playing your map. Please fix the player 6 issue right now so that I can approve your map, I am very willing to do so but that bug just impedes me from doing so.
A map will be approved after after a moderator took a look on it and checked whether it hurts any rules of map submission as well as taking a look on its quality of gameplay and terrain, often based on reviews like Sclammerz did one for your map. It can take a few days or weeks, depending on moderator activity. Usually quite fast tho.