Sorry if I missed out on anything but the code for add that is test 1 is using inline CSS however in ad_test.html there are two sections for adds,HTML and CSS.I'm trying to view the add using source but don't know what goes in the CSS space as there isn't any specific css code for that.I tried pasting the entire Test 1 in the HTML space of ad_test.html but it breaks.
TL;DR : I'm not able to preview adds as I don't know what should go in the css section of ad_test.html.
Yes in code 1 and 2 when you remove "<br>" tag code is visible at least for code 1 for code 2 there are some glitches that dont show whole code ad.
Im trying to see what is the problem but i will try to change also ad code and see what is wrong.
Codes 3 and 4 work fine, so i will try to compare all 4 and see what is problem.