A Space Between will play each track in the selected playlist and will wait (one might say insert but that's technically incorrect) a user-set number of seconds between each. Play can commence at the "top" of the playlist or from a selected track.
NOTE: This script will only work as described when the "Up Next" queue is empty. You can use the "Clear" button" in "Up Next" to empty it of tracks. This is an issue with iTunes 12.2 and later.