There's some sort of bug in the way "Threshold to count song as played" setting is interpreted. For example, setting it to "60% or 300 seconds" makes it that songs longer than 300 seconds never get registered as played. I imagine the expected behaviour is to check whichever condition is reached first, so that a 3:20 song is counted as played at 2 minute mark (60%), while a 15:00 one would be counted at 5 minutes (300 seconds). I don't have time to look at the code, so I'm reporting it here.
Thanks for reporting this bug.
fixed in http://git.gmusicbrowser.org/commit/a0959187a6
I got confused in the code about whether I was returning true for a full play or returning true for a partial play.