If an asset shows a "Missing Dependencies" icon (a yellow puzzle piece), right-click it and select List Dependencies Downloading from DLS:
For the uninitiated, a KUID looks like a glitch in the matrix—a string of characters like kuid:43933:100412 . But for the Trainz community, these alphanumeric codes are the DNA of the game. They are the unique identifiers that distinguish a generic boxcar from a specific Pennsylvania Railroad X29 boxcar from 1937. kuid search trainz