Used the new setting to make the Lab infinite,

but this brought 2 problems:
1. 2 of my previous "empty" sides(upper and left) remained empty chunks (but spawning lab-chunks again behind them)
2. I have biter nests and biters spawning in the Lab!

Yes, I realised after testing it that the black border had a bug. We are working on it, meanwile I uploaded a version with out the infinite lab change. See if you can use another save file for now and if you have other bugs have another bugs. I'm still working on the

I'm not able to get biters to spawn in the lab on version 313. Are you using any mods that might affect biter generation, like RSO or Rampant?

Oh yes I'm using RSO, sorry I forgot to mention this. :(

the mod should now be compatible with rso. It should fix this problem, but please check it out.