Nope, no need to write anything ... you already did. I just need to figure it out now. And the standard marimba range they have is 4.3 octaves, or A2 to C7 ... had to dig that up myself earlier today when one of the kids finally woke up (it is summer vacation after all.) They have at least one that's E2 to C7 but as I said before, I don't know what they'll be using. The standards for sure, the rest is a toss up.
So my task right now is to first get a setup to start testing which involves needing to either build a small amp, or just buy the thing from SFE ... might just do that. Then make a small test rig and start tweaking the code ... You've given me several pointers already, both on your site as well as on here so I think for now I just need to go do my homework and burn a few fingers.