You're trying to use a URL to a user's page in both instances, not a specific item (a tweet or an image). The Embedded Instagram and Embedded Tweet widgets are for embedding an individual item, not a user's feed. Update the URL with a link to a specific Tweet or Instagram image or video you want to embed and things should work properly.
To show a Twitter feed, you'll need to setup a Channel for the Twitter User and use the SCSocialStream post:
www.sourcecoast.com/jfbconnect/docs/post...reate-social-channel
There isn't a way to show an Instagram user feed.
I hope that helps explain the issue you're running into.
Thanks,
Alex