I like your calendar and I have recently replaced all my old infragistics calendars with the calendar extender.
I made some changes to the styles and I load my css after the default css loads so it updates the styles.
I had to set my calendar css to be output on every async postback of the calendar since your control reloads it's css file on every postback even when it's async. It was reverting back to the default styles.
If you want to see I have it on the home page of our test site http://test.meyerre.com/
I took your calendar and wrapped it in an update panel so I could do some things with another calendar when the page comes back.
I made some changes to the styles and I load my css after the default css loads so it updates the styles.
I had to set my calendar css to be output on every async postback of the calendar since your control reloads it's css file on every postback even when it's async. It was reverting back to the default styles.
If you want to see I have it on the home page of our test site http://test.meyerre.com/
I took your calendar and wrapped it in an update panel so I could do some things with another calendar when the page comes back.