I too am not sure what you're trying to do though you can achieve most types of gradient fill in FireWorks by moving the gradient anchor points around.
Select your object (block of colour)
On the Fill tab select the fill type dropdown that contains your, err.., fill-type (i.e. Solid [not a gradient], Linear, Rectangle, Radial)
Now click on the fill tool on the toolbar - the gradient anchor points will be visible and you can move these around to change the gradient flow. Different fill-types have different types of gradient anchors so play around with each - you should be able to achieve the effect you're after with some combination of these techniques.
Just shout if you need any clarification of the above.
If all else fails, try going to the User Forums at Macromedia (with your trusty newsreader):
forums.macromedia.com (for a complete list of available NGs)
Then subscribe to the macromedia.fireworks group. Any question you can think of can be answered by someone in there. Posters also include some very well known authors of Fireworks books and manuals (such as the author of Playing With Fire -- [playingwithfire.com...]
When you have probs or need help with Macromedia products, the forums are usually the best place to start looking for answers.