Very cool John! Great work - and what a fun way to collaborate with other singers/musicians!

I'm not sure what the reference track was that you recorded to, so take my suggestion with a grain of salt. But really the only critique I would give is to work on tightening up your rhythm and timing a bit.

As with any songs (or new guitar techniques) you learn, be sure to always practice with a metronome (or drum beat) at a SLOWER tempo than the original song. Be sure to practice slow enought that all of the chord changes and licks are executed at the correct timings, locked into the metronome.

At that point, repetition is your friend. Keep practicing at that slow tempo. If you spend alot of time doing that, and then go back to playing along with the track at the full tempo, it will seem much smoother and easier to execute.

Other than that - excellent work! Keep it up!

Mike