Widget problem "feed url undefined"

hi,

i´m using the latest version 2.0.6.2 and have a problem with the widget.

it say the feed url is not defined and i will show if the feed settings are correct. but in the widget i can´t choose a feed url.

here you find my site: http://timovomsee.de/files/wordpress/?page_id=157

on the right top you see the widget with failure and in the content i show for testing the entries wich will be displayed in the widget.

thank for this great plugin and your developement!

https://ww.wp.xz.cn/plugins/google-calendar-events/