A quick note: Sometimes, a specific version of an asset may be unavailable, but more recent versions can be found. Trainz is not smart enough to grab any version other than the ones found in the KUID table. You will need to find the updates manually by looking under the author's KUID. For example, you would want to look under Author: #45324, sort by KUID, and scroll down until you find <kuid2:45324:90301:x>. Be sure to keep the dependencies list handy as you browse so you know which minimum version you seek.