Ability to *move* an element on hover

A very common micro-animation effect is to 'move' an element on hover - i.e., moving a button a few pixels to the left/right/up/down when hovering. This is usually done by changing either the position (left/right/top/bottom) of the element, or its margin. Right now this is impossible to do in WebWave, because the Position and Margin areas of the Element Inspector are greyed out when we select the 'On hover' state...