I'm not sure if this is intentional, but my Moho Mines are giving out deep ore chunks before I even have the tech to process them? Is there a way to turn this off so they only output normal ores?

Same issue here

The issue seems to be related to the weird way the drills are implemented in this mod. If I place the moho drill normally as a player, it works fine, but if I use testing surface mod like the Blueprint Sandbox, the placed drill will be in a borken state and mine both chunks and ores

Hello, indeed there is a script action when placing a drill to make the ore patches work differently depending on which drill is placed. This is working fine when player or robot place the drill but othermods placing them may not trigger deep core mining script.
Not sure if this is fixable, which mods are you using to place the drills ?

Tried with Blueprint Sandbox and had this issue. Haven't yet tried with Editor Extensions because can't find the patches in editor menus

I confirm that it work properly with Editor Extensions as this is a mod I use to test mods !

I've taken a quick look at the Blueprint Sandbox and this mod does a lot of custom code to handle it's sandbox levels. I've also tried to with the mod and indeed DCMD script is not triggered and I couldn't find why and how the Blueprint Sandbox mod spawn entities.

The mod description doesn't tell how it does it either so you would to ask the mod author how we can be compatible with their mod.

In the mean time I can recomand editor extention that works very well to test Deep Core Mining !

Yeah, I usually use EE but had to use BS during MP session