macOS Support older OS's?

[ArtOfWarfare]

Virtual machine running Snow Leopards

Thank you for that answer.

I was hoping for something less involved, but I guess that's the only option, then.

 

[EricBlue]

Yes, ultimately that's what needs to be done.

You keep missing what my question actually is.

I do not have a development computer running Snow Leopard. How can I create an interface using Snow Leopard UI elements (the more bubbly, aqua elements,) that were replaced in Lion, on a machine running Lion? Is it possible?

I think you don´t need to do anything. Its the same elements, just that Snow Leopard draws them differently. I think that the NSPopupButton is almost exactly the same since OS X 10.4 (tiger) at least.

The only difference is a new bezel style constant in Lion for the ButtonCell: NSInlineBezelStyle, and you´re probably dont use that one. Otherwise you can just choose any other and it will be fine. They all work in all OS Xs since tiger.