I have MM Soundtrack edition (Feb 2014) which works OK.  The Help file says there is a "mouse mode" to drag an item to change the tempo (timestretch). And I've found elsewhere that shortcut keys ALT-7 might switch mouse mode to this timestretch option.  But it does nothing, and I cannot find anyway to use the mouse to change the speed of an item by dragging on the timeline.
	How can I do this, please?