Where are settings stored?

Application stores all the workspaces in a JSON file (workspaces.json). Preferences are saved in User Defaults. Data location depends on where you bought the app from.

Mac AppStore

~/Library/Containers/com.apptorium.Workspaces/Data/Library/Application Support/com.apptorium.Workspaces

Website

~/Library/Application Support/com.apptorium.Workspaces-dm

Setapp

~/Library/Application Support/com.apptorium.Workspaces-setapp