When developing an application for use in custom menus, you may want to open an external Window for displaying a plug-in. For you to be able to display any productivity plug-in in an external window, you need to use the following code in the menu item command:

Open external window(left;top;right;bottom;winType;title;plugInArea)
Where left, top, bottom, right, bottom, type and title are the window's attributes and PlugInArea is the plug-in area type (_4D WRITE, _4D CALC).