If you are facing this issue, it means you are using a theme that uses its own page builder. In this condition you can directly add Cool Timeline plugin shortcodes inside your page builder text editor. You can find all of our short-codes at here – http://www.cooltimeline.com
* This issue mainly happens in Divi page builder and SiteOrigin page builder
This error occurs if you are already using our free plugin and want to update it to pro version. Actually you need to deactivate free version before installing Cool Timeline Pro. Also remember to use latest version of PHP behind your WordPress installation because some errors occur if you use an old version of PHP.