Launching Storyline 3 course from a SharePoint Site

We are making training courses available to contractors outside the company firewall via an ecfpartner SharePoint site. All has worked great for years until a month ago. Now nothing launches outside the company firewall even though the ecfpartner SharePoint site itself is outside the company firewall. Any ideas of how to fix. We've been working on this for a month now getting no where. The links function perfectly within our network but are totally unresponsive outside the network.  Thanks!