I have another startup error:
https://imgur.com/a/wOuYzg6
Icon size issue, seems to be caused by the first line of k2-se.lua, krastorio2.lua may also have this issue.
May also want to change the amount of fuel cells you get from each recipe as Krastorio changed the vanilla amount from 10 to 1, same with the fuel cell reprocessing recipes, I think this is part of the reason the fuel value is higher.
I was also going to say to add compatibly for the Nuclear Fuel mod with K2, but is it seems Krastorio might already balance that mod's fuel.