In order to improve song switch times you can instruct Cantabile to pre-load all songs and racks used in the set list:
From the Tools menu, choose “Pre-load Set List” to toggle this feature on or off.
Whether to pre-load a set list is stored as a property of the set list, so you can have some set lists pre-load and some load on demand.
Depending on the plugins you’re using, pre-loading a set list may require considerable RAM. You can mitigate this by sharing plugin instances across multiple songs by loading them into racks and using the same rack in each song.
I don’t know if I am understanding what you are saying, but you select a setlist from the file menu, then go to tools to pre-load the setlist you chose, or created. https://www.cantabilesoftware.com/guides/setLists
Hmmm. Having the same problem finding the Preload menu item. It’s not an option under the Tools Menu. I AM running Performer. Must have changed with a recent version upgrade??