If you want to edit events in FL, first assign a MIDI CC number of your choice to the cutoff or whatever you want, using the double right click menu, then browse parameters and find the number you chose, right click it and choose edit events.
Alternatively, you could assign a VST number instead of a MIDI CC, then if you move that knob and go to the 'Tools' menu - last tweaked, you should find options to either edit events or create automation clip.
Hope that helps, and nice tune by the way, interesting work.
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