It is not possible to set the focused control on a fcControlDlg object, or to get/set the cursor position in a MemoControl. This applies to Formativ 1.6x and earlier versions.
Formativ 2.0, which is going into public beta, includes a visual forms designer and provides dynamic access to the controls on a dialog. These features make it possible to do what you require. Watch the main web site for beta availability.