Hello,
A binary executable file for a 285-point Zork from June 1977 will shortly be released by MIT. I found the file on PDP-10 backup tapes, and tested it on an emulator running ITS. This version may be only a few weeks old. Per Tim Anderson: “By late May [1977], ADVENTURE had been solved, and various DM’ers were looking for ways to have fun.”
Additional files will also be released, including some source code from a later date.
In related news, the final 616-point MDL Zork has been compiled, built, and played to conclusion on ITS. Welcome home, Zork!