It looks like it wants you to spawn 7 Wretches. There are rules for what to do when there aren't enough pieces, however, I'm not convinced that's what they intended to have happen in this case, for the beginning scenario.

My guess is Location 16A:3p should be AB instead of AA? Can anyone confirm?

For our first game we just ignored the extra wretch but upon further reading added a Drone later on since this seemed the only logical explanation. The first scenario seems fairly difficult to accomplish but that's probably the idea so you learn how to work together using the follow action and staying as a group. I played Marcus and went down bleeding probably 6 or 7 times but that's because we really weren't working as a team very well. If there is a misprint it should show up in the FAQ which should be available sooner or later.