I don't think there's anything particular strange here (maybe I've misunderstood tapper's first reply, plus reading the piano roll isn't very easy). Essentially what we have is:
Fm Ab Eb Db as our basic chord progression. Everything nicely in key.
It sounds pretty bog-standard and tarnce-like to me:
http://soundcloud.com/steevm/moonsnstuff
In tarnce it's very common to vary the chords over a bar, generally changing only one note - a lot is just switching to sus2 or sus4 and the appropriate minor/major. In the first bar, our variation is from Fm to Db major. But going from Fm to Db is simply exchanging a C for a Db. Again, just one note variation, in line with most of these tarncy things. The Dbsus2 following the Ab in bar 2 could also be interpreted as an Absus4 (and we have no idea what the bass is doing) - again there's only one note changed. Only the Db and Dbsus2 following the Eb represent a "big" change, but by this point the progression has already done this a few times (changing to Db or a related chord at the end of each bar) and the next chord is also the Db anyway.
I've no idea what the musical terms for these variations/transitions is, but it's definitely very common and you'll see/hear it all over the place in all types of music. JarJar is probably right though
Not sure about the timing in the original though, I shortened every second dotted eighth to be an eight note.