Hello, @marvin,
1-1 I have just checked your site now and it is working perfectly fine for me, the image is also showing fine on frontend as well, please see this screenshot: https://postimg.cc/XprCk4PF it must be the cache issue at your end nothing else. so try to clear the cache and check back.
1-2 Again, just checked your site now and it is working perfectly fine for me, the image is also showing fine on frontend as well, please see this screenshot: https://postimg.cc/HJ9ckxJG it must be the cache issue at your end nothing else. so try to clear the cache and check back.
2- And again, just checked the header builder and it is appearing and working fine for me as well, please see this screenshot: https://postimg.cc/KKfjyHVx it must be the cache issue at your end nothing else, so try to clear the cache.
Try to use this extension of google chrome to remove the complete cache everytime: https://chrome.google.com/webstore/detail/clear-cache/cppjkneekbjaeellbfkmgnhonkkjfpdn
Regards 8Themes Team.