The missing wheels. So I have created a fix and I am working with DAZ. For now, the second car and first flat car are the same base and if you load 2 number 1s and roll one of them back to the right hook up point, You can now load the liquid cargo. More cars would need to be loaded this way of course anyway but that's no excuse. I did make the second car to give everyone an easier time of things, best intentions, you know the sayings.
So sorry for any confusion many may have not even noticed the issue but it came to my attention here and I am on the fix!
How did I miss that it works with other trains?! So the Parkside Passenger Car and all will work on these tracks...? The train cars themselves aren't my style, so I glossed over it at first...reconsidering, now.