This mod break the locomotives from this other mod: https://mods.factorio.com/mod/Nuclear%20Locomotives

Their locomotives use only nuclear fuel-cell to work, but this mod change to accept other fuels and block nuclear fuel-cells!

Thanks.

This mod only targets a fixed list of vehicles. Nuclear locomotives are not on that list. Nevertheless I tried to reproduce your problem with only the two mods active but couldn't.

I take a screenshot: https://imgur.com/a/TnCRlYH

Thanks for the reply!

As I said, this mod does only touch locomotives it knows about and the Nuclear Locomotive is not among them.

I see "Singularity Fuel" in your screenshot. That looks like something from Krastorio 2. Have you tried generating a new map without Krastorio 2 active? It could be this happens because Krastorio's fuel re-balance option is enabled.

I don't have Krastorio2 installed!
Without this mod installed, this locomotive only accepts uranium fuel cell in the fuel slot!
Maybe is some interactions with another mod that I have installed, but as soon I removed this mod, everything works normally!

Thanks.

Ok, I tried again, I could reproduce the problem but the fault lies with Nuclear Locomotives itself. I'm adding a second fuel-category to the vanilla locomotive and when there is more than one, setting only one, like NL does, will be ignored by the engine.

I opened a more detailed bug-report for it here.