Thanks very much indeed, that was very useful. This command puts the menu in the right position, without error messages.
The effect is limited: Some buttons open dialog boxes, but
drop-down lists do not drop down, and I cannot achieve any formatting
effects in the textarea box. Furthermore, the format of the tools is a
bit off: buttons are taller that the toolbar on which they reside;
hence four rows of buttons need five bars. If there are obvious reasons
for this I would be glad to learn about them; if not, I will engage in
some more debugging before returning to the group for some more advice.