I just downloaded, unpacked, and uploaded the events_calendar module to my site root(r115). After a little config, it mostly works but I'm getting the spinning progress icon(see attached) and a JavaScript error from FireBug:

jQuery("#calendar-widget").datePicker is not a function
[Break on this error] .datePicker({inline:true, startDate ...rt : start_date, rangeEnd: end_date}) 

which corresponds to this line in the 'calendar_widget.js' JavaScript file:

jQuery('#calendar-widget')
.datePicker({inline:true, startDate : '01/01/1990', endDate: '01/01/2999', month : month_view, year : year_view, rangeStart : start_date, rangeEnd: end_date})

These were my steps:
1. I copied over the necessary .ss templates to themes/mytheme_events_calendar/templates and made my layout changes.
2. Copied the events_calendar/css/calendar.css to themes/mytheme_events_calendar/css/calendar.css and changed my new .ss templates to reflect the new location of the css.
3. Removed the css call from the event_calendar/templates/Layout/Calendar.ss and CalendarEvent.ss (these would override my css layout otherwise)
4. ran /dev/build?flush=1
5. Created a new Calendar page and CalendarEvent page in the cms.

I get the same issue even if I use the default install without creating custom templates.

Chris.b