I expect Song Actions “Start at Start Marker” option to apply to the next song.
This doesn’t work - see screencapture.
If I have misunderstood this, then please explain how “Start at Start Marker” works.
Regards, Michael
Hello, I just checked my project. It works as usual. However, I’m a MacOS user.
Well, this is apparently a Windows thing then… 
When a Partis selected, and that Part belongs to a different but the currently active Song, the new Song is selected.
When a Song is selected, it will locate to its Start Marker.
And when “Autostart” is active, or the Song became selected because of a Song End action “Start next Sont”, it will then start from there (or zero, if not set).
In your video, you set “Start at Start Marker” for the 1st Song, this option relates to the current Song, not the Song action of the following one.