Hate to open a can of worms here, but I'm looking over this for purposes of forwarding to attorneys, and am thinking that "distributed under a free license" is too legally vague (since the CPDL license itself and the Creative Commons license do have some restrictions and are not entirely free. Don't want to draft the goal in a way that could be read to exclude the majority of scores on CPDL.
How about "under a license that allows unencumbered performance, printing, duplication, and derivative works, provided proper attribution is provided." ???