I couldn't place turrets down
Viewing post in Ralph's Terrible Mistake jam comments
You need to first collect scrap before being able to build defenses. The amount of scrap you have is labeled in the bottom right corner of the screen. On level one you gain initial scrap from by clicking a nearby orange barrel. If you had scrap and were unable to build please let us know. Haven't been able to replicate an issue with building while having scrap.