I can't seem to figure out how to fill this train with steam other than spawning "superheated steam" and putting that in the train by hand

use a pump

I tried that. let me try with just this mod.

Isolated it to just this mod and it still won't fill.

what mod and game version are you using?

https://photos.app.goo.gl/6J9GGANBqPC1Ln1L8

here's a few things to test:
- the pump only connect to the rear half of the locomotive
- the locomotive must be on a perfectly straight piece of track
- try without the graphics mod

if none of these help, send me your save-file

here's a few things to test:
- the pump only connect to the rear half of the locomotive
- the locomotive must be on a perfectly straight piece of track
- try without the graphics mod

if none of these help, send me your save-file

based on my testing you must not have the train on even the slightest curve and the train must have the pump on the back 4 of the total 6 slots available to be pumped. I also noticed the animation doesn't work for the pump deploying. I tested all of this with and without or the graphics mod.

But yes i did get it working in vanilla. I am have trouble with it in my modded testing world RN would you like to take a look at that?

Does your mod only look for "pump" I use bobs and angels and when I use any higher tier pumps they don't work. I tracked done the problem to bob's pumps. in the bob's logistics mod. Is this a mod interaction bug?

• correct, only the back 6 slots attach. Due to technical reasons i need to generate multiple invisible tank types - one for each possible connection permutation and tank size. with 6 attachement slots thats 2^6 = 64 tanks. if i were to allow all possible slots, thats 4k different tank types. which is not really feasible.

• pump animations (i assume you mean the filling arm) dont work. that is a known issue but nothing i can do there.

• loco must be straight: correct. but usually no issue because you refill
  at a station.

• pump types: yes only vanilla pumps are supported.

please keep in mind that i took over the old Diesel Trains mod an just updated and modularized it and expanded on some functionality. I have not designed nor reworked the core functionality and don't really intend to unless something is clearly broken.

Hint: If you need faster refilling, enable tender mode and attach a fluid wagon to the back of the loco and fill that with steam. the loco will pull from there, but only if it also has at least a bit of steam in it