Free Waltz by Babelism / PAHC is the eleventh (or twelfth level depending on whether you include SAVE AS) level that you visit while playing Over Again by PAHC the intended way. At the end of this level you get 1/5th of the final code in Over Again.

This is just a fun cube timing / ship challenge. It's not that difficult so most GD veterans should be able to beat it in under 100 attempts.