VSE: transition FX suddenly don't work?

I’ve been rendering out 1/4-size sequences for my Kata project and laying them down in the VSE against my pre-recorded music track in order to get the timing perfected. All was going swimmingly until all of a sudden a “Cross” effect added between strips doesn’t work, even though one added between similar strips in earlier sessions was just fine.

A little testing showed that none of the transition FX – Gamma Cross, Add, Multiply, etc., – would work, either in scrub or playback (ALT+A).

Anyone else ever experience this? Anyone have a remedy? I was hoping to keep this whole project in Blender but if the VSE is being cranky I may have to find another route.

You didn’t happen to accidentally press ‘H’ while the strips were selected, right? I found out by accident that I could mute strips in the sequencer and started all over again before I found out what was going on.

Deleting the effect strip and adding a new one doesn’t work either? Just thinking out loud…

What stroke me was that the properties panel appeared no longer floating, but in the buttons window (but transistions worked). Maybe that’s a new feature… Do properties appear correctly for you?

The sequencer properties were moved from a floating panel to the buttons window awhile back (2.46?), so that part is normal.

I closed and reopened the file after deleting the single transition strip I was trying to use, then added a new one (no Mute) and it still doesn’t work, regardless of type. I’ll try loading everything in a new file and see if that helps after I get some more renderings done.

This is just a scratch track edit to get the animation timings down (I’m cutting to the music), but I planned to use the VSE for final edits as well. If the transitions are busted I guess I’ll move it all into the Compositor, which I find very reliable, just slower to set up for everyday stuff like cross-fades and cuts.

EDIT_________________________

I opened a new file and placed the same resources in the VSE as in the original file, and the transitions work fine in the new .blend. I guess maybe the glitchy file would be useful as a bug report example. It’d be a real beeyotch to have things go flooey like this after editing an entire flick in the VSE!