Not all mods wants to use the "new industry" cargo. The "FMC 50 'boxcar" wants to use new cargo without hacking. The 60 'High cube Boxcar will not accept the new cargo without hacking.
Here's the mesh problem in photos:
The train in the above screenshot is carrying limestone. The empty wagons are the "H12 open hopper" unhacked it will not carry limestone.
This train is fully loaded with Limestone, the "empty" H12 hoppers have been hacked (hex) to carry limestone but there is no defined mesh for limestone for this model. The loaded H12 hoppers are visually "empty." . ̶I̶ ̶c̶a̶n̶'̶t̶ ̶e̶v̶e̶n̶ ̶f̶i̶n̶d̶ ̶t̶h̶e̶ ̶m̶e̶s̶h̶ ̶f̶o̶r̶ ̶l̶i̶m̶e̶s̶t̶o̶n̶e̶ ̶i̶n̶ ̶t̶h̶e̶ ̶f̶i̶l̶e̶s̶!̶
(update! mar-17-2018) It can render limestone!
To remove "new industry" cargo from vanilla wagons you need to modify a file to "new Industry" in the scripts folder. I thought it was weird when MaikC's centerbeam flats came with "cars" & "Com_Auto" as a load option! Imagine that! Now I know why!
So yes you can easily change boxcars, tank cars, and covered hoppers. Not much time required. Hacking buildings can take a while.
I got all my answers by post # 3!
@ 'Vitaro
Do the city industry and commercial buildings accept only 5 cargo max? I tried 6 & the game crashed.