Asset has duplicate attached track at track $(INDEX).
This error results when a KIND SceneryWithTrack-derived asset specifies two or more attached tracks between the same pair of track vertices. This construction is never permitted by Trainz, and so the requested configuration cannot be fulfilled.
INDEX is the zero-based sequence number of the vertices container at which the error was detected.
Note that in cases where the track vertices move (such as a turntable or transfer table) it may be possible for this scenario to exist only at specific instants within the animation. Current asset validation will only detect this problem if it occurs in the default state of the asset, meaning that it is possible for such an asset to pass validation but still encounter problems at runtime. The error may be visible as a brief incorrect repositioning of a segment of track that occurs during the animation. This should still be considered a fault in the asset construction.
When repairing legacy assets which exhibit this error, the simplistic fix is to remove the duplicated segment by deleting one of the vertices. Such a change will, however, result in a different number of attached-track entries, which means that existing instances of the asset saved into routes may encounter loader conflicts with the updated asset. A more robust fix is to adjust the duplicated segment by replacing one of the vertices with a different attachment point so that the number of attached-track entries is unchanged. This fix depends on another attachment point being available at a location within the mesh that allows for a similar path to the original, while not creating duplicate segments.