I've downloaded the modpack like 3 times, uninstalled and reinstalled java and the AT launcher several times as well, and it still won't work. Every time I click play, the launcher closes and re-opens.
Same here, but after reinstalling with 0.8.1 instead of 0.8 (which ATLauncher automatically chose) it seemed to work fine. I don't know what version you're using but 0.8.1 works for me.
I've downloaded the modpack like 3 times, uninstalled and reinstalled java and the AT launcher several times as well, and it still won't work. Every time I click play, the launcher closes and re-opens.