Well I have to say my FPS game engine was almost my first blitz game. I only made "fledged hoverboard" and "csp world editor" before. Although the CSP FPS engine is a playable game engine, it's still very limited, and the sourcecode is already a huge pot full of spaghetti, sotosay. Whenever I want to add something new, I have to take care not to override some globals etc. A typical beginners design mistake.