Add your HTML in Dreamweaver rather than in Fireworks.
Thank you for your feedback. You're right in a way that I find I have to tweak my upper/lower case letters in the Dreamweaver source code. But let's say I want to add another graphical menu selection to my drop-down menu (created by editing my 'slice' in Fireworks with its own .html file under my site directory 'images' folder)...but, as a result of invoking the 'Round Trip' function between Fireworks and Dreamweaver, the new menu selection also now appears in my Dreamweaver's index.html page --- after 'Save' , and as it should do (...BUT...overwriting all upper-case letters in all URLS within the index.html file---all the ones I had to tweak before in the Dreamweaver index.html source code ---- so, it appears every time I want to create a new graphical menu selection (or even edit an existing one for that matter) in Fireworks...the round trip writes over all my previous upper/lower case URL tweaks in Dreamweaver. If I could somehow manage the upper/lower case issue within Fireworks--and maintain it between closing and re-opening Fireworks--that would definitely solve the problem.
As a practical piece of advice, it's better to have your URLs in all lower case. Sometimes, people want to type them in and if they don't get the case right, they won't get the page. It's a very common best practice to use all lower case specifically to avoid that problem as well as having to remember or record what your special casing was for a page.
Try surfing around some of the highest-traffic sites in the world. Check the URLs... How often do you see mixed or upper case?