Hi,
This file looks like it came from a program that purports to export MIDI from audio files - am I right? Unfortunately we have not yet found a good piece of software that can successfully perform this operation. I don't say that to put down anyone, it's just a very, very difficult task to solve, and no one has done it satisfactorily yet. Celemony's Melodyne editor does some incredible audio analysis, but even the MIDI output from that is less than stellar for trying to get sheet music. Note timing, pitch bends (for instruments that have vibrato) and other issues just make the transcription of audio to MIDI an extremely daunting task.
With this file you can tell just by playing it in Composer (or any other MIDI application) that a lot of overtones were mistaken for actual notes (giving chords for what should be single notes) and the timing of notes is quite bad. This file would take an enormous amount of work to try and get any legible sheet music from it. Notation Composer does have a new Rebar feature that can help with timing issues (you can read about it in Help/Users Guide, and use the Index to look up "rebar"), but that is most useful with files that only have timing issues, not the compounded problems that this file has.
You can read our page at
http://www.notation.com/Articles-AudioToSheetMusic.htm for how to get sheet music from audio files.
ttfn,
Sherry