I am currently facing the same problem.
I just downloaded a new script ROS hack.lua and use the GG app and excute script, but I have the error like the above mentioned, while the other script for ROS hack is working perfectly fine.
And about the "Do not load html file as script"? I am bit confused! No. I am totally confused! Isn't it the script (.lua) must be executed by using "execute script to run the hack? I just don't understand. Thanks bro.