The "Older Version" just had different styles applied. In 3.5.3 you can import and export styles and it even comes with several including the "Older Version (Classic)" style.
Since this is a new installation I would delete what you have and upload 3.5.3. There are several styles that come with Atahualpa in the styles folder. See post 8 of the
FAQ thread for more information.
After installing go the the New Versions and Updating thread and apply the bug fixes listed there.