Flamenco Sketches

Ok so this song the improvising section is just repeating the whole "Progression"

So this does like 4 bars I think of Cmaj7, then like 4 bars of Ab7, then like 4 bars of Bbmaj7. ok so thats just the first part and its got some chords in the middle but:

How do I handle improvising over this, do I just use the arpeggios of each chord or do I switch scales?

So now the part that does D and Eb each in one bar for like 16 bars.What do I do here?? D arpeggio and Eb arpeggio ?

Stupid song, I love it but, I don't understand it!