Who can Help?The rule is very simple: When it is your turn to place an AP, you may place it on any vacant eyeball space. "Any vacant" is even underscored.
When I want to place a AP on the Glaciation field do I have to start on the right side and then wait for three rounds until it can be used (When it reached the most left position)or may I place it on a place of my choice?
So you may place it on the "migration 2" space if you wish to migrate last, or on the "migrate 7" space if you want to migrate a lot. And on the "glaciation this turn" space if you want to do it this turn (if it is empty) or on the "glaciation next turn" space if you prefer to do it then.
Since the rule says any vacent eyeball space, they mean just that.