Pretty neat but some observations (which ironically have nothing to do with the spell itself):
Change the icon to an active version - ReplaceableTextures\CommandButtons\BTNFreezingBreath.blp
Change the screenshot to one in which you can actually see something. Once you take a screenshot, don't edit it. Perhaps just copy-paste only a part of it but DON"T edit it so people can actually see how the spell looks.
Oh, and still, I have a tiny improvement for the spell itself. Instead of using a variable (PointofTargetNova) change the "Offset by 100 towards PointofTargetNova degrees" to "Offset but 50 towards (Integer A)*25". I also mentioned a smaller offset to assure that the units close to the hero are affected as well.
Overall, a very nice spell for the first attempt. I have nothing to comment. 5/5