On Xerox devices, where scanning from the Umango embedded application, you may experience a situation where a scan completes through the ADF and Umango does not progress and complete the workflow.
This situation can occur when the scan is initiated using the Xerox device's hardware "Start" button instead of the Umango start button. Scans should always be started using the green "Start" button at the top of the Xerox panel within the Umango embedded application.
This feature has been updated. All versions released after version 5.3 support the use of both the Umango 'Start' button and the green hardware 'Start' button located on the device. Enjoy! :-)
Link to this article http://umango.com/KB?article=73