Based entirely on the error message he is receiving, it's this line that's the problem:
https://github.com/Afforess/Misanthrope/blob/refactor/libs/biter/base.lua#L95
One of the variables that table.insert is looking for is not a table, and is expected to be a table, as "table expected, got nil ...

Preview of an upcoming feature: Though it's a little buggy right now and doesn't line up with the map when oriented east-to-west; only north-to-south (or south-to-north) works at the moment.

(collection will be simulated though.. will still be artifacts on the ground because I don't want to have to actually detect and remove them for later depositing because if the squad dies ill have to spawn the items back in again as dropped loot)
You could give the bots actual inventories, so you ...

Well, what chemical reaction can't be reversed with a little finagling?
Take Water, for example. You can split it into hydrogen and oxygen through application of electricity, or you can put them back together through application of heat.
Plastics are often melted down for recycling, often to form ...

Reverse chemistry machine when?
With that, you could covert any excess oil-products into solid fuel, but when you need the oil products, boom, chemistry recycled. Gone would be the days of tiny fluid tanks, you could store far, far more petrol in a steel chest.

Heh. With this mod you can make liquified solid fuel, and then use solid fuel to heat liquified solid fuel in a boiler to power your steam engines. No water source required.

I am enjoying this mod very much. As for cliffs, I am making a separate mod using the API and code-hooks you've set up so far, it's far from complete or ready for testing, but I don't think there's much additional coding needed on your end to allow outside mods to use your code to make stuff that ...

No, error does not happen in new version, though I don't see what you did to fix it

Your most recent "release" on Github has a bug. This is 0.0.2, which I downloaded to try to get a handle for your code to get started on the above.
When I try to place a downwards powerpole (will test with an upwards pole in a moment) I get the following error:

error when running the event ...

I'm guessing by the fact that the OP was last edited today, and the DemoSave was apparently "not downloaded yet", the demo save has been updated and you should try the new version.

I was just thinking today that it would be cool to have a mod that had this mod as a prerequisite.

I've been watching Avaak's Let's Play of Rimworld Alpha 13, and in that game there are mountains/cliffs/stuff you can dig through like your underground surface, except on the "surface" surface.

So ...

I've uploaded a small update. This adds teleporter gates (long-ranged belt-to-ground), and not much else.

You can also find the enemies.lua file, but it has been commented out of data.lua, so is non-functional. Adding them back in as is causes a crash to the game with no error message, you can try ...

It's possible once I complete this mod, I will make a deal with someone to make a texture pack or addon for that sort of overhaul; but this mod's objectives aren't so grand as to be total replacement.

Progress update, I was working on enemies but due to a crash with no error message and no clear ...

So any plans to add flying or burrowing enemies that can travel between surfaces? Or even just enemies which spawn in each surface?

Edit: Also, compatibility. If I want something to be able to spawn in the sky (like... mana nodes from Wizartorio), or if I wanted to be able to find an ore ...

Maybe I wasn't waiting long enough.

Here's an album of un-edited screenshots showcasing everything this mod has to offer (so far) .
Starting with recipes for the shafts up and down (might want to crop those), then showing that there are no recipes for the chests yet?

Then a fresh sky-block, no ...

Bug (?) report while gathering screenshots. Or issue report, whatever.
If you go to the sky without some way to build a platform, you're stuck. You need to move away from the shaft and back to it before it will let you move.

Haven't tried going underground yet, still getting screenshots. Will ...

Ill grab you some. Not right away, you may need to crop or edit them too, but Ill get them soonish for you.

It could be difficult to program a way to make drills/elevators different colors based on levels; perhaps possible, based on this person's skill, but hard. I would enjoy this as it would be a nice touch, though.

I don't agree on limiting depth; no point. Realistically, you could make a mineshat ...

I was just about to tell you I just edited them in, but you edited in you noticing that.

Name: Wizartorio
Version: 0.1.0
Factorio Version: 0.12.33
Licence: MIT , because I don't know how this should work. :P
Dependencies: Base
Description: Adds magic and resources to the game.
Author: Flabort
Co-Author Credit: Macros, GotLag, Vas, Afforess, and the rest of the IRC
Artist ...