Depends on your definition of "broke".
Good idea is to DL the KR Setup EXE from somewhere, and go to Control Panel. Choose NetmarbleSDGO and click Change instead of Uninstall. Click the middle option (Repair) and when it prompts you find the folder the EXE is in. The setup will replace corrupted files in your installation. This works for when the game fails to start and keeps throwing error codes at you.