The arithmetic combinator does not give 0 with the remainder of dividing a multiple of 10 by 10 (for example, 40 mod 10 = 0, but the combinator does not give 0)

Understood, thanks for the explanation)

This may not be a bug, but the steam boiler uses 6 units of water producing 60 units of steam (previously 60 units of water per 60 units of steam).
This allows you to connect 200 steam boilers to 1 water pump (previously the maximum was 20).