Welcome to the Forum!
Yes, you can:
In the Scenario Editor, klick the blue box in the middle left flyout, then another window opens to the right side of your screen. There you see the developers as a dropdown list.
Select RSC and then search the GP9 pack and activate it by marking the checkbox, and you´re done!
Unbenannt.jpg
If any further problems occur after that, close Railworks, start new and clear the blueprint cache:
klickme.jpeg
No comment about my artwork

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