I had a unique situation present itself which required me to figure out a way to make CMS Builder work within an existing Wordpress website. After a bit of research, searching the forums here, fumbling around with code and installing/uninstalling various Wordpress plugins that were supposed to help (they didn't work), I finally found a solution (that's EASY). So I thought I'd post it here in case anyone else searches on this topic later.
The solution was a Wordpress plugin called "Allow PHP Execute" (https://wordpress.org/plugins/allow-php-execute/). This allowed me to use the CMS Builder code inside a regular Wordpress page WITHOUT having to painstakingly put shortcode around every piece of PHP code (the other plugins required this task).
Hope this is helpful for somebody--and hope this doesn't sound "spammy" lol (it took me a lot of time to figure this out)