I've got it, finally, by putting

IF USED('formversions')
USE IN formversions
ENDIF
SELECT formver, formvername ;
FROM fileconstants ;
WHERE formchar = scanrun.formchar ;
INTO CURSOR formversions

into the Init event of the formverlist, which has a RowSource of formversions and Rowsourcetype of 6-fields, and the above code plus

THISFORM.formverlist.INIT()
THISFORM.formverlist.REQUERY()

into the InteractiveChangeEvent of the combo box.

No doubt you were all correct with your various suggestions - Once I started over with a blank form to get rid of accumulated accidental extra stuff that may have been buggering up my previous tries, I made rapid progress. My lesson - fewer events with less code is mo bettah. Thank you all.