Your post gives very little information that I can use to fully answer your question.
Please define "unsupported"?
I am assuming that you are using TANE or later.
What does Content Manager say about the status of these kuids?
If they are described as "Installed from DLS" or "Modified" (which means created by you, modified by you, or imported directly from somewhere that is not the DLS) then you can delete them BUT be aware that they may be needed by other assets.
If they are "Built-in" or "Base" then they came with the install of your version of Trainz and cannot be deleted.
If they are "Payware" or "Packaged" then they were installed as DLC from the Trainz Store and cannot be deleted by Content Manager. They can only be deleted by using the Trainz Store to delete the entire DLC package that they came from.
To check if an asset is needed (a "Dependant") by other assets:-
- In Content Manager select the asset (a left mouse click)
- Open its drop down menu (right mouse click on the selected asset)
- Select the option List Dependants
This will list all the assets that will become faulty if the selected asset is deleted.
