My immediate reaction on reading your piece was to go back and stare at that painting again, because for whatever reason my own instinctive interpretation is that in 'Blue Green Music' the flowing pattern in the centre is moving downwards as though being syphoned out of the pointed end formed by the harder, more precisely constructed outer shapes. In these colours I see nature, perhaps being cleared to make way for the dark, looming skyscrapers you mention, which would be rising on three sides, enclosing and containing, while the living was swept away. The left hand corner looks like a river outside the city and the point of the funnel could be diverting to join that.