"Look at Me!" Achievement

 

I have been playing Fallen Enchantress: Legendary Heroes on my Steam account and trying to complete all the achievements, but "Look at me!" achievement doesn't work at all. When I try to share a custom unit on my Facebook account got an error message on browser that reads:

 

"Can't Load URL: The domain of this URL isn't included in the app's domains. To be able to load this URL, add all domains and subdomains of your app to the App Domains field in your app settings."