This tutorial is primarily for canvases 300x225.
Dimensions for 400x300 canvases are in italics

Open Fireworks, then open a new document with the following properties:

(Or 400x300px)

Draw a standard rounded rectangle, with the following properties:

(W:161 H:16 X:118 Y:55)

Select Gradient > Linear.

And select the following settings for the gradient:

I've used blue as an example, but you can use any colour, but keep it the same along the gradient.
(Same colour throughout / Top opacity 100% Bottom 80%)

Here's how to make the gloss:

Duplicate the layer, by selecting the rectangle, then Ctrl+C then Ctrl+V

Now an ellipse with the following properties (Don't worry about colour at the moment):

(W:235 H:120 X:80 Y:9)

Select both the duplicated rectangle and the ellipse:

Now select Modify > Combine Paths > Intersect

You should end up with something looking like this:

Give the gloss path the following properties – Fill > Solid > White and Opacity 30%

You should now have something that looks like this:

Next, paste the transparent logo you are wanting to make onto the canvas:

Select both the rounded rectangle and your icon for the logo, then hit Ctrl+Alt+2 then Ctrl+Alt+5 to centre it. You should get this:

Then simply add reflection and you’re done!