Some assets might require extra content to work!
All Assets except signal lights and the actual yard layout are found under train transport tab. The signal lights are found under props and track layout in intersections.
There is no need to subscibe to all of the assets, some assets have different versions for ppl who doesn't want extra content for the assets to work!
I highly suggest to download NoPillars mod at: http://steamproxy.net/sharedfiles/filedetails/?id=463845891 and enable Overlap mode to be able to plop assets almost anywhere.
To plop the signal lights ingame, you will need More Beautification (found here http://steamproxy.net/sharedfiles/filedetails/?id=505480567 )

Added the two functional trains to the collection eventho they aren't exactly ploppables.