It's an overhaul mod that makes large changes to the tech tree and items, so you would have to add it in to the tech tree with equivalent science requirements and convert recipes to use equivalent Nullius ingredients. The Robot Logistics and Personal Transportation techs and recipes should help as references to determine that. I would enjoy using these spidertrons to construct the final stages of the terraforming factory complex if you would, thank you.

Hi

Are you able to construct spidertrons? you could enable easy recipes and create Constructrons from Spidertrons if that is the case.

Spidertrons are craftable, but enabling easy recipes does not make a recipe for Constructrons. I think that's because Nullius by default disables techs and recipes from other mods unless if they mark that they are compatible. https://mods.factorio.com/mod/nullius/discussion/60f4f3c7c7e9f57568f624a5

Hi

I'd like to try and get this out with the next update for you.. I am completely foreign to Nullius.. perhaps this is best discussed in the discord in real time https://discord.gg/m9TDSsH3u2