1d. Why is there a %20 in my URL?
%20 means you have a SPACE in a file or folder name.
To fix this, open Dreamweaver and make sure all files are closed and you have defined your site.
Rename file in Dreamweaver
In the Files panel, rename the file/folder without the space. When prompted, update files.
Upload new files to server
Upload the file and folder and all files that link to it.
Delete old files from server
Changing local file and folder names DOES NOT change them on the server, so you will need to delete the old files/folder from the server.