Hello,
thank you for reporting a problem with the app. There is a known issue with showing progress of the scan, as it is based on number of folders in root directory it may look stuck when it comes to folder with huge number of files. We had a testing phone where scan took 15 minutes as it came to folder containing 5 tousand files. As folder was removed (some old log files) scan took up to 15 seconds. We are adressing this issue in coming release, there will be also an text information about what is scan doing. Please wait for this version and then report us the text information that will be displayed in the moment it gets stucked. We hope we can figure it out together.
Cheers!