PointsAtMarkers is a script that adds points to selected track envelopes at the position of the marker.  To use, first add markers to the timeline at the desired positions.   Markers can be added manually or during playback by entering M at desired positions.  Once markers have been added, the script will add points to the selected envelopes.  Conversely, markers can be added at envelope points for selected envelopes.  All video and audio track envelopes are scanned.  There is also an option to include event envelopes such as velocity and transition progress.   There is also an option to quantize the resulting markers or envelope points to the nearest frame.