Thanks for the bugreport!
Thanks, it was a lazy typo in the language file. Good spotting!Hokuso Development 3150 Series says that it can only be extended with 3050 Series units, should say 3150 Series units.
It's true that it's possible, but it's not possible to move the train out of the depot when the eight car consist condition isn't met. I didn't take the time to look into the possibility of making a callback when the train is longer than eight cars in the depot to produce an error message. It is however mentioned in the readme and parameter settings that Keikyu trains have a 12-car max. length and others 8 cars (with Chiba Express and a few older trains as exceptions).Keisei 3000/3050 4-Car unit can be coupled onto 3000/3050 6-Car (Also vice-versa, 6-Cars can be coupled to 4-Cars, shouldn't be able to according to the description) and 8-Car units (8-Car units cannot be coupled to a 4-Car, shouldn't be able to according to the description).
Cheers!
Toni