Trouble inserting images in Timemapper

Hi, trying to create a timemapper to show events in our work area over 2015, but I’m having trouble getting images to appear. I have uploaded them to the web, and included the corresponding link in the Media (Image) category, but they simply don’t appear. All of the other fields (Date, Title, etc) are working fine.

Google spreadsheet is here: The Year in Financial Transparency - Google Sheets

Any ideas?