Itunes not downloading episodes for a podcast

Looking at your top episode, the 'enclosure' tag (which should contain the URL of your playable media file) reads:

<enclosure type="https://archive.org/details/Top20Forwards" url="https://archive.org/details/Top20Forwards" length="0" />

The URL you give leads to a web page with an embedded player: this won't do. You must provide a direct URL to the media file. You can get the URL from the 'VBR MP3' link in the sidebar at right. In this case it's

https://archive.org/download/Top20Forwards/Top%2020%20Forwards.mp3

You should change the https to http - this will still work.

In your 'enclosure' tag the 'type' must read 'audio/mpeg' and the 'length' should be the file size in bytes (without commas). You will need to do this with all your episodes; at present iTunes does not recognize your episodes as having media and so won't show them.

Your feed can now be subscribed to in iTunes and the episodes appear, so you've sorted that problem out. However you will be rejected because of your artwork. The URL in your 'itunes:image' tag is

https://s14.postimg.org/x7leraq0h/147225300577122.jpg

This image is 800 x 800px - the minimum required is 1400 x 1400 px. I would also advise avoiding the URL beginning with https (secured connection) but using http - the server you are using is forcing https even if you enter http. You could change the image on the same server and see if it's accepted.

The image is at https://s12.postimg.org/6y8z532hp/SCHWARZ_cover_1400x1400_HOCKEY.jpg

This is still 800 x 800px. If you are uploading a 1400 x 1400 px check that the server isn't reducing the size (it's been known).