Ted, I just re-read your first message carefully. I may be guilty of
jumping to a misconception! First, try downloading with Data-cam.exe
that I detailed above. If it works, then do this:

Get Cambridge Aero Explorer running. When the window opens, LC Tools,
LC Options, LC General. Use the down arrow on the Recorder Com Port box
to select the proper com port for the adapter (1 or 2 if you changed
the Com port as described in the DOS Window downloading post, 4 if you
didn't). LC OK.

Now connect the adapter to the Cambridge 20 and turn it on. In CAE, LC
Recorder, LC Connect, and report back what happens. Hopefully things
will work!

-John