I added this mod to a current game and all trains were marked "fuel-less"... why? I don't understand which kind of fuel is needed since nuclear rocket fuel was not authorized :/ . I tried with normal rocket fuel and it didn't work at all...

This mod limits nuclear fuel to nuclear locomotives.
Use rocket fuel for normal locomotives.

Hi. I tried but it didn't seem to work... I'll try again and come back immediatly after. (All my loco have either nuclear fuel or normal rocket fuel)

Edit: I tried again with any fuel (wood/coal/rocket fuel) in automatic or manual: all trains start to stop when they run out of their current active % energy bar. See the example in this image:
https://imgur.com/a/nUv4Wyt

Edit: to be fully informative (and maybe find the bug?) when I put a new locomotive on the tracks, and any fuel in it, it works. That "bug" only affects already existing locomotive (ie locomotives which were active before the mod was added to my playthrough list of mods.)
Can you fix this? I rather not change all locomotives manually :/

I can't reproduce the described effects.
- build 5 locomotives without any mods enabled and fueled them with all fuel types
- enabled Train overhaul, all except the one with nuclear fuel kept using the existing fuel

PS: locomotives filled with nuclear fuel don't show no fuel warnings as the game seems to check if there is something in the fuel inventory regardless if the locomotive can use it as fuel.