OK - I "solved" it - in typical Fireworks fashion...
Turns out that if you have a slice on top of another slice, even if you TURN OFF the slice on top you can't export the slice underneath. You'll THINK you're exporting it, but no file gets written. The solution is to keep dragging the slice you want to export to the top of the stack of similar slices.
Also turns out that if you have a slice on top of another slice, and you turn off one of them, and select the other one and resize it, the one that's turned off ALSO gets resized. It's invisible. You didn't select it. But it got resized.
Not surprised - this is Fireworks, the buggiest piece of s..oftware... that has ever carried the Adobe name.
For the future, I guess I'll have to give up this way of doing things. Too bad. It's nice to make one layout, put all your varying elements as layers in the same position, and just turn them on and off and export them individually. It works in ImageReady - no foolishness with non-displayed items interfering with displayed ones, or getting resized. For the future I'll just duplicate items next to each other instead of stacked, in separate files for just that purpose. Heading text-as-graphics, header images, etc.
Why can't somebody FIX this program, or give us something else that DOES work...I'm amazed I don't hear more complaining about it, but maybe the PC version works better than the Mac...
Why are you creating same size/overlapping slices to toggle on/off when it's the Layer content that is changing (your 8 headers)?
Just one set of slices will do, then toggle the header images (that already fit the original slices).
But each slice needs a unique name. So don't I need a slice for each corresponding layer/header? Or should I just name each slice as I save it?
You could do it that way, or have a page for each header. I would just
keep separate pages. This gives you a great deal of control over each
unique header/ page design. Toggling layers on and off is very much a
Photoshop workflow because PS doesn't have the capability of utilizing
multiple pages for different designs.
Alternatively, create a single new page and you can just stack each
header one above the other on the canvas and generate individual
slices quickly in that manner. It won't be a page that looks like a
cohesive design, but the end goal is the image export, not maintaining
a mock up design, for that page.
Correct - you can just rename the slice(s) before export.
Jim;s suggestion will work well, also. Duplicate the Page, it automatically duplicates a second set of slices which you can rename separately from page one. Toggle the header graphic and your good to go. No need for overlapping issues as the Slices will be contained on a page by page basis.