Hi Konstantin. I now understand.
Precompose a copy of your layers – Fabrik above Masks. Set Masks Track Matte to Alpha (the white windows should now wipe on)
In your main composition have two layers – the Precomposition above Fabrik. Set the Precomposition’s mode to Exclusion.
That should do it(?).
Hi. I think what you want to use is a “Track Matte”.
Turn your blending mode to normal.
On the Fabric layer, next to Modes/ “Normal” box, is the Track Matte box, twirl it open and select Luma Matte.
To make it procedural:
Precompose your text layer A.
In your main comp have two layers of the text layer.
Change the lower layer to black and add your blur.
Now when you change the text in the precomposition your main comp will automatically update.
Hi. Select the solid layer, then go to the project panel and select your matte. Holding down alt drag it down and over the top of the solid layer and release it.
Hi. You might try precomposing the final image, add the Curves effect to the precomposed layer and drag the bottom of Chanel = Alpha to the right to get rid of the shadow on the alpha. (?)
You can create a floating panel with the waveform visible. Precompose the layer, then ctrl+drag the precomp’s tab away from the main comp and you will have a copy of the waveform visible at the same time. You can then use either of them to go to the time(s) you need.