Whoops - I guess I must have spent a little too long making my tea and did not see your updated post.
If you are having issues installing z4root, you may want to surf for the apk with your Edge, then download and install right on the Edge. xdadevelopers has a direct link
It is possible that you have root access, but, in addition, you must also change the permissions on the files/directory to allow you write access. By default, the keylayout and keychars are set to read-only.
This is where something like the root explorer app comes in handy. It has a nice button at the top that toggles between "Mount R/W" and "Mount R/O"
Only once you set files to R/W will you actually be able to save changes. Root access will allow
you to change permissions, but does not automatically change default permissions - this you have to do after you have root access.
I hope this helps!