I've uploaded a new version with these changes. Keys 1 to 9 will select a save slot, F5 will save to that slot, and F8 will load. Additionally, save/load can be mapped to gamepad buttons, and the current slot can be chosen from the pause menu.

I recommend running "hibernator_console.exe" from the command prompt, just in case one of LÖVE's subsystems gives any kind of error message in the event of another application close. (Warning: If you double-click on the exe instead of going through cmd, the console will close when the game closes, taking any messages with it.) Additionally, it might be a good idea to change your save slot every 15-20 minutes just to ensure that the save isn't corrupted somehow.