Hi Bob,
Not having TC this is a little guesstimate, but still valid as far as I have gathered of info.
You need to open the CMP program - not quite sure what it is called in TC, but it is the program one uses to add things into TC.
the program that opens when a cdp file is clicked on for instance.
Or, a download is taken place of a Trainz file.
Either way, CMP came first with TRS2006, and was kept for TC and further programs too I imagine.
Witch CMP came a new way of dealing with content in/out of the game, and in order for you to access the config files for any content you need to enter into CMP and find the map there.
Then open it for Edit In Explorer (in TRS06 it is Ctrl+Shift+E) by either the shortcut I just wrote or by right click the item you want to check out and click on the choice Edit In Explorer.
This will open a new window with the files belonging to the item you need/want to edit.
Hope this helps some?
Best wishes
Linda