Impressive!
Yes, there does sound like some dissonance, especially noticable in the piano portion (the rest fits in really well.) The harmonic minor is not usually used to write a whole song, it's purpose is to help the harmonies in the minor key to get back to the tonic.
That said, this is a very awesome usage of the key, and I give you many props. I wish I was daring enough to try a scale like this.