CloudFlare ServerShield Error when activating domains

[~ Andrea ~]

Hi,
I'm getting an error after the install of the ServerShield extension on my Plesk 12.0.18 server.
I've successfully installed, activated and linked the extension with my CloudFlare account.

After activating the first domain, now when I try to activate another domain I'm getting this errore in the Chrome console:
Uncaught SyntaxError: Unexpected identifier - servershield.php:18
Uncaught ReferenceError: CF_LANG is not defined - servershield.js:28

And the web panel remain like the screenshot.

Many thanks for any suggestions.
Andrea