I cannot colour biters dynamically... if I have a fixed number of biter forces I can pre-define the colours and create copies of the prototypes and set their colours but its a huge amount of work :(
What would be nice is if the biters had a 'force' layer/mask on them, which I can 'tint' with colours dynamically. each biter sub-faction can have its own unique (and randomized) colour.
Regarding Krastorio 2, I don't know why my code would be deleting biomass resources, I think what could be happening is my code changes the force of the spawners (biter generators) and then Krastorio's code doesn't know where to look (because the force is not just "enemy" anymore)