Thanks, I see what you mean. However, I did not managed to export the 2 stages yet.
The export of the slice for the "out"-stage works fine, but when I try to change the blend to the "over"-stage, nothing happens (select the slice, try to change the blend, but the blend stays "normal").
I think I'm doing something wrong (I'm a newbie for Fireworks

) so I will studie the "blendfunction" of Fireworks CS for this particular case. I'll let you know the result.
Jeanmarc