7 rounds is tough from the perspective of organizing your list, but it works just fine technically. The lists are updated after each round, and as long as a player on your list is still available, he will remain on your list, in the same order that you set.

Remember to utilize your drops properly, so you don't end up with 7 1B's. Should your draft list empty out, the robot will choose for you. The robot chooses the highest PB rated player available at any position you do not have filled.
I'm not entirely sure how the robot picks players once every position is represented, but my guess is that it looks to back up each position with the highest rated player available.
If you are leaving at the beginning of the draft, I might recommend being starting-pitcher heavy on your draft list. The reason I say that is because it seems that positional players of "comparable" talent to pitchers have a higher PB number, and all the decent pitchers will be gone by the time the robot gets to them in the draft.