Is it possible to copy a setlist from one project and paste it into another?
That includes copying across songs, recordings and midi presets.
No. You can move a set list to a different project, but that's mainly in case you create it in the wrong project. Your songs and MIDI presets can be shared across multiple projects, so that usually eliminates the need to copy them. If you want to access the same set list with all the same documents and recordings from multiple projects, then I'd reconsider your organizational strategy and whether you should have separate projects.
I have started a new project and want to add songs that are in an existing project. When I look in the new project, it has no songs, no recordings and no midi presets so how do I retrieve songs, recordings and midi presets from an existing project?
You can edit the existing songs and MIDI presets and you'll see a Projects list that you can update to share the items with the other project. (Recordings will be shared along with the songs they're attached to.) On the website, you can update projects for multiple items using the batch update options in the left column.
Thank you, Arlo. That does the trick.