Update:
Now, I knew the Applix1616 had composite video, but it required making up a cable that goes on the standard DE9 connector (Pin 7 is the composite signal, Pin 1 is ground). So I decided to make up a cable and try it on the TV in our kitchen. The TV has a few dead vertical lines, but it does work and has composite in.
Lo and behold, the video test mode worked!
Video test screens (Video on Youtube):
And when I changed the run/test switch, power cycled and then did a reset, I got the following:
Applix1616 Level 1 reset screen:
Based on that, looks like the ROMs are V4.5a. Of course, I’ll check that all once I get it properly running.
Note: I didn’t have a keyboard connected for this test. I think that I’ll come back to the Applix1616 tomorrow, give everything a once-over and then see where I can go from here.