I love that you put in so much of time making all this.
Just one suggestion. Some of the elements require scrolling while filling in the form. What if the result/code on the right scrolled down with the user? I actually faced problems seeing the result as I made changes, kept having to scroll up and down.
Better UX with the same UI ;)
If you have a basic understanding of web code, this tool is priceless
Pros:Easy UI, lots of options
Cons:Need to have a basic understanding of code