And we don't really know what they had to do to make it work. The <audio> api is not known for its robustness and accuracy.
Our hack from October was really simple (two small python modules), but we spent all day compiling midi libraries to use with python. That was definitely not easy work.
You can write to /tmp. But since most people are also doing that, /tmp/date gets overriden frequently. I'd recommend mkdir /tmp/CZ-18; PATH=/tmp/CZ-18:$PATH; And then you can figure it out :)