A movie may be moved by selecting it and dragging. Selecting the movie will cause it to jump to the front most layer of the page. You can deselect it by clicking on the page, clicking on another item or choosing Deselect Movie from the Edit menu.
To resize a movie, select it, then click and drag in the grow box in the lower, right corner of the selection.
Holding down the shift key will constrain the move or resize. (See “Shift Key” under “Special Key Functions”.)