Doesnt go anywhere

Its just some powerchords put together... It needs more to it than that, and the melody doesnt make sense. Sorry to sound harsh, I feel it could be improved if you developed it a bit more, maybe with a clean section? Maybe with a second melody? It needs to have some kind of climax to it, instead of just being heavy all the way through.

Are these real instruments?

I think this would sound better on real instruments, or maybe theres something a bit too clean about the recording process?

Good arrangement, I was thinking of doing this tune myself at some point. Please check out my stuff and comment back :)

Good.

If you try to keep the input volumes low, and keep the channel volumes down, and then only turn it up in the main mix, that should help with the clipping. Either that or you E.Q. it so that there is less bass. Another technique that might help would be to use a bit more compression maybe? You have to remember that the important thing when recording is to keep the input from clipping, NOT the final volume coming out (altho compression can help with this).

As far as the arrangement goes, I think it would benifit from replacing the piano with a lead guitar (just really for stylistic reasons). The harmonies you've used work well, esp. the half-time style section- VERY METAL! :)