Sounds like the script is trying to access the marcobelli website but is unable to. It is a badly done script* when it throws a script error on a missing internet connection, though.
Check your internet connection and firewall, also check in the After Effects settings that scripts are able to access the network.
Oh, and also it is best to contact the author for these questions. Here in the forums we can only guess, the author knows what is wrong.
*the missing check for an internet connection is badly done. The script itself, when everything is working as it should, might be great.