Animate Layer Opacity with Markers

I built this when I had to step through 70,000 frames of Skate Warrior and duck out the bad frames from one file, so that another would show through. If you also have a stupid pointless annoying project like that, this is the preset for you!

Base Opacity is the opacity value for frames where no Layer Marker is present. Frames with a Layer Marker will take the Marker Opacity value. You can also blend back to the original opacity values from the layer, which can be animated. Bypass reverts to the layer opacity.