I honestly tried everything I can to recover the save data and it is gone AF. I remember where I was... Are there any cheats, or could someone perhaps provide save files? I had completed the Frykt system and no further.
I didn't have any idea so I brought you question to the Discord and I'm happy to tell you:
Spoiler
Alt-U: Unlock a world in Creeper World 3. Press when ship is orbiting a planet.
Greetings from The Shire
I tried that...
[spoilers] Alt-U, turns planets green when you exit to the menu and come back to the game, but does not actually unlock shielded planets or progress the game. Still stuck. [/spoilers]