Yesterday I completed the 2nd movement. The biggest challenge I had was trying to create the indefinite pitch quality of drums on the marimba. I was able to approximate the highness and lowness of the various drums by using a single pitch on the marimba, but this sounded more melodic rather than percussive. So I added some notes to create irregular interval content which gave the marimba a more drum-like quality (measures 37-40). The low drum was used as an ostinato in in measures 41-60. The example on youtube had the rhythm as 6/8 but I changed it to 5/8 to add an intensity that the counterpoint on the youtube example created. The ending is a repeat of the first part of the movement. I lengthened the ending notes of the first bird call in order to make the transition smoother. The movement fades away with a repeated figure.
The youtube url is http://www.youtube.com/watch?v=mX2lsG1Lw_8. I suggest that you copy and paste this into a separate browser window so you can compare it to what I wrote.
To see and hear what is discussed, go to http://www.cooppress.net/guatemayablog.html