У вашего броузера проблема в совместимости с HTML5
@1:38 you can see a cool trick to gain extra workers without building something permanent that would take up critical space. I repeat it a little later in the vid. You also regain 7 units of wood. Woe is you if you haven't collected every bit of manna by level's end.
Make notes of where the caches are: gold time + 6/6 caches are unlikely without prior knowledge of their whereabouts. But anything is possible. :)