There seems to be an issue building 3-8-0 train. The building station tries to make a 1-8-2 train.

Also I keep getting a "Missing Fuel" error. The 2k of solid fuel and 10 nuclear fuel don't seem to be enough..

Otherwise I really like this mod. Question, is the Max amount of trains able to be build 25. I am using LTN and need about 90 trains.

Huh.. I just tested doing a 3-8 train and it seemed to work correctly - can you upload your save file?

On the number of trains, yup - the slider only goes to 25 but the internal limit is actually 1000, you'll just need to type it in the text box (and you can also use circuit signals to trigger scaling regardless of the configured count).