1. Please note that "No tittle" template has no title in its structure and the header comes over the content of the page but by default a little padding is left for the content by default(which can be removed by css).This is why starting to put content in the no title page would makes the header to appear over the content .
2. Please disable ajax registration from wplms -> miscellaneous :
3. It seems cache has been cleared and the changes is refletcing in your site now .
4. Please note that by default edit page is open with the wplms front end edit nut your pages are built with the visual composer ,So please use the visual composer front end edit to edit the page by first goto back end edit page and use the visual composer for the front end .
refer : https://www.youtube.com/watch?v=xcSYuI-2SuM