Where to Begin with Modding Planet Crafter?

[SwissxPiplup]

Hello there, I'd like to create some more building pieces for the game Planet Crafter, I believe I have adequate knowledge on how to create the models in Blender, but I've no clue where to even begin with importing them into the game, nor setting up snap points, or how to make walls, ceilings, and floors change when snapping to other pieces (if two rooms are connected, the connecting wall vanishes). Does anybody know what sort of additional software I might need to begin this journey? If it's even possible.
I know if I could extract the models and import them into Blender, that would take a huge chunk out of the work since I would have the proper scale and dimensions to work with.

Thank you.