Stir the graham cracker crumbs, melted butter, and brown sugar until evenly moistened. Divide the mixture among six dessert cups and press it into the bottoms.
Sprinkle the gelatin over the cold water and let it stand for 5 minutes to soften.
Add the hot water to the softened gelatin and stir until the gelatin dissolves completely.
Blend the cottage cheese, Greek yogurt, vanilla protein powder, key lime juice, maple syrup, lime zest, and vanilla until completely smooth.
With the blender running on low, pour in the dissolved gelatin and blend for 20 seconds, until evenly incorporated.
Divide the key lime filling among the prepared cups and smooth the tops.
Refrigerate the pie cups for at least 4 hours, until cold and firmly set.