Hey! I'd like to help you but i need a bit more info:
1. What happens exactly when you try to start?
2. Where is the game installed? (e.g. C:\Program Files\... or somewhere else)
3. What's your hardware and Operating System? (GPU, CPU, RAM, Windows/Linux)
4. Check for logs in C:\Users\YourName\Documents\My Games\Kitten Space Agency\Logs\ . Does the directory exist? If yes: what are the contents of the log file?
5. If the logs file is empty: check Windows Event Viewer (Win+R > eventvwr > Windows Logs > Application > "Find" (on the right side panel of the window if you are using windows 10) -> KSA") for entries with source ".NET Runtime" or "Application Error" around the time you tried to launch