As I've been learning Popcorn, I discovered what I believe is a small but annoying bug, and I wonder if anyone else has encountered it, or if perhaps I just misunderstand something.
One of the great things about Popcorn is that you can change parameters on the fly.  In particular I can change the Blend Mode back and forth from Alpha Blend to/from Alpha Blend Unlit.  When I do this, the correct key appears in the timeline, and the display changes correctly.  So in that sense it's working correctly.  But as I manually move the playhead, the current value as displayed in the Popcorn 'Modify' window does not change; it just stays at whatever the most recent setting was.  I spot checked other parameters, and they all change to constantly reflect their current value at every point in the timeline.  Only the Blend Mode remains frozen, oblivious to which side of the key the playhead is on.  The annoying implication is that I cannot tell which Blend Mode a key affects unless I actually run it and see what the display looks like.  Annoying.
Tim

Yeah, that is a bug. One thing you can do, is to select other prop and then back to Particle effect (making sure the Object Related Track is grayed, so that effect does not disappear from timeline).
This way settings would reflect current Blend mode from timeline when you come back. It is also annoying, but at least you do not have to rely on visual.

Oh, great idea.  I never thought of that.
Tim