Use Design mode to design your ProcessMaker Screen. Design mode is the default mode when a ProcessMaker Screen is created or edited. While in Design mode, use the Design setting section to configure controls that you place into your Screen Builder canvas.
Use Preview mode to view and test your ProcessMaker Screen. Test how your controls function as a form user would experience your Screen during a Request.
Furthermore, test how the ProcessMaker Screen's controls you configured in Design mode interact with JSON data models. ProcessMaker represents ProcessMaker Screens as JSON data models. You can view any JSON data model in Preview mode to test how a Process's JSON data model or another ProcessMaker Screen's data model interacts with your Screen. Viewing the JSON data model can be helpful to see how values are entered into the ProcessMaker Screen as well as to use that JSON data model in your ProcessMaker Scripts.
Use the Custom CSS mode to add custom CSS styles to a ProcessMaker Screen.
Use Watchers mode to add Watchers to that ProcessMaker Screen. During a Request or while previewing the ProcessMaker Screen, a Watcher monitors when the value of a control in that Screen changes or receives a value, acts upon a Data Connector or runs a ProcessMaker Script using that control's value, and then outputs its result to another Screen control.