To build this, you'll need the wla-dx assembler from: https://github.com/vhelin/wla-dx

The latest release is v9.6, but I used a relatively recent commit:
https://github.com/vhelin/wla-dx/commit/01f7fd16a111ed2cbb81b4c07ed5e793bff5d6bd

v9.6 may or may not be able to assemble this.

Music was done with xpmck. To modify it you'll need "xpmc" in your path.
http://jiggawatt.org/muzak/xpmck/

Graphics were done with ppm, though this tool is abandoned...
http://www.villehelin.com/ppm.html