I just upgraded to SGSV 5_7.  I have noticed that now, I cannot add a Date Range to any pages.  It appears to be a bug.

When I enter the date range configuration and click update, no date range selection is displayed.  When I return to settings, the Date Range enabled checkbox is unchecked and all but the Clause field are empty.

Ugh ... you are correct.  I will post a correction revision very soon..

Update: I have released a fix - version 5.7.2

Thanks for the feedback.