What do you use to edit GoPro videos?

I bought my GoPro Hero3+ Silver Edition last Friday, made a few videos, downloaded GoPro Studio, then it said I "had" to download QuickTime Player, and started learning how to use Studio after watching many YouTube’s tutorials. It all worked fine as I learned a few simple things to do.

Last night, I filmed the family putting up the Christmas tree so I had another video to play with but when I tried to use Studio, nothing works now. As soon as I try to download clips … the screen says GoPro Studio not responding. The screen goes full size and then shifts to smaller size w/o me doing anything. I am also getting a message asking if I want to save a file called "AutoSave." I never even heard of that file. Then the screen goes to a smoke looking screen.

I’ve never had issues like this computer-wise so are you guys using Studio having any issues? Or what do you all use to edit your videos?

Any help will be appreciated.