After update of test project to new build one (second) of the calendars stopped showing appointments
The demo seems to work fine: http://www.daypilot.org/demo/Calendar/MultipleCalendars.aspx
Can you specify how to reproduce the issue?
This might not necessarily be related to showing multiple calendars. Could you please check if there are any JavaScript errors?
You can also try to record the network traffic using IE and send the NetworkData.xml file to support@daypilot.org for inspection:
http://kb.daypilot.org/81542/how-to-record-network-activity-using-ie-developer-tools/
Looking at it more I see that the bug is a resource calendar that has actually a problem, it was a second calendar and it does not show any events. Changing it to the Day calendar displays events again.
This bug is fixed now, see also:
http://forums.daypilot.org/Topic.aspx/1909/newest-daypilot-pro-7-3-2840-0-resource-calendar-does-not-s