[TYPO3-calendar] Updates will not be shown from Google Calendar

[Markus]

Hi,

we are using a Google Calender to organize our events. I have created a 
cal external calendar with the public URL to our Google Calendar.

Now we have the problem, that no changes of the events are displayed in 
TYPO3 cal FE...

I have declared a cal scheduler task in the scheduler and it is running 
as it should, but there is no synching visible...

Thanks for any hint...

Regards,

Markus