Interesting execution of platforms placing mechanic. :) Also, I think you are checking exactly for 3 seeds collected, instead of >= 3. Because in the first level you can skip placing one platform and collect 6 seeds, which will claim "not enough seeds collected" on trying to place a platform. Also you could enable placing them by click as well, as you move them with a mouse. It's also slightly too slow/low, jumping/gravity. Although might be an FPS issue? Good job though! :)