Browse through the commercial break playlists, make sure that everything has been scheduled according to your settings. Make the manual adjustments. Whatever you re-arrange in the commercial breaks, will override the scheduling algorithm settings.
The Traffic Log Editor will display only the hours where a specific campaign appears, so that you can keep a tight eye on the schedule, and check if everything is perfect.
The scheduling algorithm will always do its best to avoid any scheduling conflicts, but in real life, if there are no other spots to split the spot group (piggybacking spot), you'll have the final word on what to do with the schedule.
In case you're required to do the last second change, you can add any active spot directly to the commercial break playlist.