Hi Kencomp,
I seem to have the same problem, I cannot find it in either Trainz 2010 or Trainz 2012, it says it has been installed, but it cannot be found, even if I search for them, but there has been occasions were it cannot recognise the Duchess pack serial number, especially in Trainz 2012.
I run Trainz 2010 in Native mode, with the favourites button not clicked, and the gold star not displayed, so I am as lost as you, I might try another install later tonight and let you know how I get on. There will be something we have missed, once I find out, I will let you know.
Joe Airtime