It seems your site has many improper tags. Could you please try to fix them first? Please check your contents and ensure you put the correct tags there
Will this happen to all my sites that feature one of your templates?
Do I have to check the code all the time if I am changing an image or creating an article?
No, this is not the template problem. When you insert article, make sure you put the html tags correctly, for example if you open a <div> you should remember to close it with </div>, etc
So I have to write everything in html when creating an article?
Also checked validator with html source of site and everything is correct. So why is validator displaying these problems even though they are correct?
But look at the menu titles - Special Feature , Main Menu , Poll etc there are too big. Why would that be?
I put a new article under lisburn distillery on main page and it is fine, but the title, written by and date etc or too big as well. Is it the module settings or a template setting?
By the way thanks for dealing with all this crap, really appreciate your effort and time.