John,

I have just created a menu and 2 forms, the first form has ShowWindow=2 and a button that launches the second (modal) form. The second form has ShowWindow=1 and WindowType=1 (modal), in the Init() of form1 (the top-level form) I put the following:-

do samplemenu.mpr with This

When the second form is active the menu is disabled and you cannot select options until the modal form is cancelled.