You don't have to do the top action to be able to do the bottom action. Just pay for what you want to do.
Right, we understand that - the player in question had no resources at all, so couldn't do any bottom row action. We were therefore wondering if any of the top row actions could have been taken.
Also you can't trade since you have to place resources on a territory where your workers are. (Home base is not a territory). You can do anything that doesn't require the workers or anything on the map sure.
Ahhh, gotcha. That makes sense. I keep forgetting that the top row action doesn't mean the bottom row action happens INSTANTLY - that there's a sort of 'pause' in-between, hence combat happening only after ALL units have moved, and not the moment a single unit occupies the same territory as an enemy combat unit.
Thank you both for your clarification. It's a minor thing but it helps a lot.