Huygens XXL Mission script - problem to run

[Dirty Laundry]

Hi,
I??ve downloaded the script of Adirondack and tried to install for running in Celestia vers. 1.32 but facing problems:

a) My Stuffit Expander does not help to install acc. to given file paths as WinZip would do (I??m on OS X) - any workaround?

b) when trying to install the components manually (the CELX file in the resources folder and the extras in the extreas folder) then starting Celestia I receive a message: "please verify this is a valid script"...
but it does not run.

Many thanks for your tips - I??m a Celestia beginner!

Greetings

Dirty Laundry