Sorry. Noted. I did search! I swear!

So I tried to start a sandbox game to scope out possible resource dead type game, try and get all the settings correct before I launch into an unknown map with them. After making the game, ensuring the variables are set, I press Generate, and a map loads. However so does the message:


Error while ...

It was one of the reasons why I posted it in General to begin with. I wasn't trying to promote my stuff as more get a challenging map.
After re-reading my post though I do kinda promote the channel a lot more then I thought I had

Guess I learnt my lesson, do not post late at night!

So I record a few YouTube videos every now and again, and in all honesty I've kind of got bored of my usual spiel. I want a fairly challenging map, something to excite and hopefully make me come out of my 'comfort' zone.
I'm fairly happy keeping it Vanilla, but if you think a specific mod might ...