prog8/examples/cx16/chunkedfile/testdata
..
readme.txt

You'll need to put the titlescreen data files from the 'musicdemo' project into this directory.
The musicdemo is on github: https://github.com/irmen/cx16musicdemo
The four files are the two ME- and the two DS- TITLESCREEN.BIN and .PAL files, and are generated by running the makefile in that project.