Hi there,
Kindly open up new threads for additional questions as it will help us to focus on each issue and give you a better support which you deserve. Having a long threads makes the maintaining job harder and also it will be harder for the other customers to find the correct information if they have similar issues. You are always welcomed to reply to this thread to follow up the same question.
To answer the 1st question, you need to go to the header builder and change the bar from Absolute to Relative to force the rest of the content go below the header and not behind it.

We will be more than glad to answer the rest as soon as you open up separate threads for each.
Thank you for your cooperation and understanding.