I have fixed the bug in the code: I noticed that you are setting values to math.min(65535, value), but something seems to round to the nearest 1,000 so the value ends up as 66,000 which is too big. Changing the code to set to math.min(65000, value) fixes the problem.
Loading Krastorio 2 still failed with an error about the icon_size for personal-submachine-laser-defense-mk1-equipment,
so I added all the submachine-laser-defense items to the ignore_items list.
Krastorio 2 does not unlock a landfil recipe until you have done a lot of reaearch, and the landfill is very expensive. So I added landfill to the "fish -> individual items", overwriting the recipe so that you can convert 9 fish to 1 landfill right from the start.
With these changes, Krastorio 2 is playable with Fishblock.
Note for 7ower3efender: if there are errors which mention a certain item, then adding the item to the ignore_items table in data-final-fixes.lua might get the mod you want to load.