3 issues: feed and custom channel URL

Hi,
I’ve setup PowerPress, everything seems to work fine apart from the main thing: the rss feed is empty, the podcasts don’t show, you can see it here: https://www.doingbuzz.com/feed/podcast/
So I tried to setup a custom chanel URL: https://www.doingbuzz.com/tag/podcast-doingbuzz/feed
With no avail: there’s a huge bug which modifies the URLs, it is a total mess. When I paste this URL in the appropriate field it becomes
https://www.doingbuzz.com/feed/httpswww-doingbuzz-com-tagpodcast-presse-doingbuzz/ !!!!
Please explain how I can make https://www.doingbuzz.com/feed/podcast/ work