I have fragments of workings for two piano sonatas from the 1990s before circumstances led to a loss of at least 95% /of my material.
This is a canon which was to be restructured as Scherzo and Trio for my second sonata. I set my sequencer to repeat my improv twice one higher, one lower so I had to play anticipating how it would sound together
https://youtu.be/QjNf7wA9nOw
This was going to be the finale of the first sonata - it was made of complex fugal counterpoint which was then cannibalized into variously diminished and augmented episodes. This dense contrapuntal soup was then gradually pushed towards a set tonal ceiling which eventually diminished it to a single rhythmic tone. Then using phase shift new motifs were created - this was a very early stage of composition.
https://youtu.be/I0IsrJ4wPK4