G-Metrix is not working on my laptop.

I am trying to get GMetrix to work on photoshop but it just doesn't seem to work at all. Either it doesn't work on my MacBook because it thinks it doesn't have permission from admin (me), it doesn't work on my school's computer lab desktops (which is weird because it works great on the desktops for this specific class), or it doesn't work on another windows laptop just because. The closests I ever got was changing the version of photoshop to an older one but even then it crashed and froze and never showed any of the tests questions or anything. I tried contacting tech support and my professor but they have not been the best help and I'm running low on options.