I have made it executable, nothing happens when I click it??
Are you talking about the
light package? It is available in the repos:
sudo pacman -S light
Yes, the one to control gamma on your monitor.
run it in terminal and maybe it will throw off some error(s) that you can follow up on.
What file have you made executable?
If you installed it through the package manager, there shouldn’t be anything needed to make executable yourself…