Don't know if it is bug or feature :) but when there is no fuel in steam loco, there is no visible level for water tank (normal hud or inventory).

it's a known bug from the networking systems, there isn't much that can be done at this point without adding a significant amount of overhead to servers.

Sometimes it's nice to find out I'm full of it.
There was actually a couple lines of code that messed up when it was sending the data in a number of ways, I had previously thought it was an issue with how the data was sent, it was a rather easy fix.