Ok so i downloaded it and put the GPP folder into my Applications folder and i opened Trem 2.1.
After i opened it, it had a black screen and then it closed Trem and showed the message in the screen shot.
After all of this my mouse acts like its in Trem and the sensitivity it like 1 instead of it moving normal it moves really slow and i have to restart my computer to fix the problem.
Hope that helps.