There doesn't seem to be any fish in most of the water. Can the LuaSurface.regenerate_entities specifying fish be called on chunks post tile change to do this?

some areas do generate fish and others don't this may be due to the way the mod alters tiles. i would guess that only tiles who were originally water (or connected to water) will contain fish?

Correct, but calling regenerate_entities should update the trees and fish to account for the new tiles.

A bit late, but I'll try this out! If it's really that easy it should be done tomorrow (because I'm going to sleep first now) :D Less than 2 years after asking! xD

I just checked this out, there are two calls, one for decoratives (which seems to add more each time you run it?) and one for entities. So for now I run both each time a chunk is generated:

local positions = {event.position}
surface.destroy_decoratives({area = event.area})
surface.regenerate_decorative(nil, positions)
surface.regenerate_entity(nil, positions)

I'm making more changes today probably, so I'll release this later today.

Cool, yea I'd completely forgotten about this also.

I honestly didn't know there were discussion on here, so yesterday was the first time I saw any of the messages here. I turned on email notifications now, so I won't miss everything again.

It has been released ;) I created a script that automatically makes the zip, so I can more easily release often now :P