Your game has potential, but the passcode riddles are too hard. It's irritating that I mostly have no idea what the passcode could be. "Action levels" (those where you mustn't get killed by enemies) are fun, but I didn't like "riddle levels" (those where you only have to guess the passcodes) and I skipped them. But then, I met a bug - in the level on the picture, the PgUp key didn't work and the PgDn returned me to the previous level. Please, could you help me? What's the passcode on the door that I'm standing in front of?
I recommend you to make the riddles easier next time. Otherwise, good job!
By the way, the lack of music in the game isn't a big problem because it's a sneaky game, so the game can be silent. Don't worry about that you didn't put any music into CyberHack 63!