Sorry, I’ve never heard of this option before. Exactly where will I find this “add horizontal divider” option? see post below
With regard to your second question, if you can’t find a solution using the forum search please create a new topic for this separate issue and we’ll do our best to help. (Clue: search for “horizontal menu centred”.)
Please try to remember to start a new topic for each separate issue that you have. We like to keep each topic in the Help Center focused on a single subject. We find that separating each question into a separate topic keeps the information much clearer and easier to follow. Also, it really helps other users to find information and it prevents threads from wandering down Tangent Lane. If you can’t find a solution using the forum search, please always create a new topic for each separate issue that you have.
Thanks.