I’ve been using CC for several years now and originally did modify my emails quite a bit. They have evolved much over the years and most things work fine with their GUI interface so I don’t edit as much HTML as I used to. But with a little work, you should be able to modify it how you want. I would suggest starting with a template and then modify it to fit your needs. If you have specific questions let me know and I’ll be glad to try and answer them.