Thats right. The whole group (column) goes up for auction. When a player is won, the player from the same tier (row) that belongs to the next group on the list goes up. Make sense
Each auction is run in it's own thread. You make a bid by replying to the thread for the player you want. Bids must follow the contract rules, and you can never bid more than the cap space you have at the time of the bid
I'm in Hong Kong at the mo, so internet access will be limited. Hope some of the other mods can keep an eye on the bidding in the early stages to make sure nobody gets off track.