for those who might need a sound player with positional marker points, I enclose a working test patch.
For setup and rehearsal I need to jump to specific positions in the music. So I designed the marker actor to jump to the exact position, and also to jump to the position 2 seconds before the marked position.
For testing purpose I extracted the relevant parts of the patch and added simple projections as proof of concept. Just use an audio file of your flavor and have fun with test sound player advance .