None of these programs run with a v6.78 ROM setup. v8.79 is required. This program was covered in The ColorCue newsletter: Vol. 6, No. 2 (Mar/Apr 1984) : part I Vol. 6, No. 3 (May/Jun 1984) : part II Vol. 6, No. 4 (Jul/Aug 1984) : part III "A Roadmap to successful installation and use." Vol. 6, No. 5 (Sep/Oct 1984) : part IV "Conclusion" 4THED.PRG -- Launches into 8080 fig-forth 1.1.0. From there one can enter FORTH commands, eg 3 4 * 2 + . (prints 14) N4THED.PRG -- Superficially, same as 4THED.PRG. I'm not sure how it differs. TPAL4.PRG -- Superficially, same as 4THED.PRG. I'm not sure how it differs. It is a lot larger, so presumably this one has the Pascal stuff cooked into it. TPAL4T.PRG -- Superficially, same as TPAL4.PRG. I'm not sure how it differs.