Fireworks CS4 Resources
Using Adobe Fireworks CS4
Extending Adobe Fireworks CS4 (adobe.com)
Drag a behavior handle from the selected slice to the edge of the same slice or onto another slice.
To create a swap image, drag the handle to the upper left edge of the same slice.
To create a disjoint rollover, drag it to another slice.
Select the state of the swap image and click OK.