ColdFusion Express is a new deployment option for ColdFusion (2018 release). It allows you to quickly set up a development instance of ColdFusion without running a full installer. See Installing ColdFusion Express.
At the end of the 30-day trial period, the Trial edition of ColdFusion automatically becomes the Developer edition, a free, full-featured server for development use only. If you want to build and deploy applications, purchase either ColdFusion Standard or Enterprise edition. Learn more about the different editions of ColdFusion and purchasing options.