I made a Planet base in creative and though it just uses basics I can't spawn it in solo game because 'Illegal Blocks' might that be a replacement green core? I had to replace the base starter block because I didn't want it on the floor. So... help!
The core is fine. It'll be crops. It's always crops. Crops are illegal. You can also use the (`) console command: prefabinfo 'NameOfBlueprint' To get a list of illegal blocks in the blueprint.
No crops, But after dismantling it piece by piece... it's the 'Personal Cargo Box', the one that looks like 3 school lockers. Who would have thought it would be something so ordinary.