Still without posting some code it is very difficult to find where is the
problem. Try to create a small sample that displays the problem here
http://demo.qooxdoo.org/devel/playground/#Hello%20World-ria
Also it is a good idea to also subscribe to the mailing list here
https://lists.sourceforge.net
Without code is a bit difficult to see what is wrong but I guess you need to
call placeToWidget in your menu.
http://demo.qooxdoo.org/current/apiviewer/#qx.ui.core.MPlacement~placeToWidget!method_public
Also you may want to have a look at this example how menu placement works
http://demo.qooxdoo.
