I am wondering whether I simply misunderstand the rules.
I started a new game, and double clicked on Village Hall, and it built immediately.
Next turn I click on Marketplace, and it says "Can be built" so I try to build it. I try both clicking and double clicking, nothing happens.
But when I double click Upg Barracks, that builds instantly.
Could it be that "Can be built" is not accurate, that you have to build all of the top row of buildings first? I am pretty confused as to what is supposed to happen.