Request for help: how to change passenger density on platforms

[drbarryk]

I've searched as thoroughly as I could, but despite finding a few references relating to changing passenger density on platforms when creating or editing scenarios none of the manuals, forums, or tutorials had a clear and complete explanation. I can't get the right side tab that has the density percentage option to open. If someone could please offer a step-by-step sequence to adjust passenger density it would be most appreciated.