We plan to open the game up for modding sometime post-launch. We do not know yet to what extent you will be able to mod the game. There are some purely technical issues related to engine and internal tool enhancements that do not easily fit the modtools paradigm. We have looked at it close enough to see that it is non-trivial and we will have to pick it up again post-launch. Right now we are completely focused on finishing the game.
And, dev console: confirmed.
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