Did you try the plus version as mentioned on that page?

   Customizable Shortcuts: https://addons.mozilla.org/firefox/addon/customizable-shortcuts/
   Key config: https://addons.mozilla.org/firefox/addon/key-config/
   Keyconfig: http://mozilla.dorando.at/readme.html
   http://kb.mozillazine.org/Keyconfig_extension 

Please reply and tell us whether this helped you!

See also http://kb.mozillazine.org/browser.backspace_action (2)

I am wondering why I need to do an "add on" when I want to undo something that has been done by Firefox. I have removed these short cuts in Windows and the difficulty it seem is downstream. Besides, I do not want to change a single shortcut. I want to remove them all. In writiing this one note I had to back track and fix the spelling because the cursor jumped about all over the place. I would say oh... 8 - 10 times. It is frustrating as hell.But thanks for trying to help. James

It has been suggested that I attach an "add on". I did this. Now it seems I need to register on this page as well. My registration for this site and for Firefox itself seems to be insufficient. Did I miss something ? My mother did assure me that the little drop on my head was nothing but who knows ? I am sitting watching the snow fall in Vancouver, BC just now and thinking who really needs this aggravation. These things are not only supposed to make you rich but our lives easier. Well, that was the thought that crossed my mind. I will go on line and see if I can find a solution

For paging back, usually you need to disable the Backspace key from operating the Back button. See cor-el's post: https://support.mozilla.org/questions/987351#answer-537172 for a link to an article on how to do that.

For this --

"In writiing this one note I had to back track and fix the spelling because the cursor jumped about all over the place. I would say oh... 8 - 10 times."

-- it sounds as though it could be Home, End, any of the 4 arrow keys, Page Up or Page Down. If you happen to hold down the Ctrl key, additional shortcuts could be an issue.

But your description reminds me of an issue that can arise when you are using a laptop, which is the touchpad responding to contact with one of your palms as you are typing. If you have a touchpad that is supposed to be inactive, can you confirm that it is disabled?

Thank you for the idea. This may very well be the issue at hand. Now to figure out how to disconnect my laptops touchpad.

Let you know how this shakes out. James

I use a double thickness of file card stock, cut to the size of the touchpad, to keep my palms from hitting the touchpad.

Hello again. After much to do I have managed to disable my touch pad on my Vaio laptop. I will now see if your observations are correct. I sense that this is so. So for now, I thank you much for seeing the trees within the forest. James

Good Day,

I have disabled my touch pad yet your suggestion of card stock is rather brilliant I think. Since the touchpad has not been in the way, I have had no jumping about of my cursor within a text field and no paging back and forward short cut keystrokes. I think this just might have worked.

Thank you very much for your time in answering my query.

James