Are you still looking for clean sound FX Brash? There is a library over at TheForce.net: http://theforce.net/fanfilms/postproduction/index.asp I haven't checked the files, but there may be something there for you.
I also watched your arena clip, and if you don't mind, I have some feedback as well:
I thought Dooku looking concerned when Padme got cut by the creature didn't really fit. He has no connection to her, whereas Gunray does. You already have him upset over defeating her creature, so why not have him be happy with the creature cutting her?
I think you made a bit of a mess of Anakin's "story" in this scene. There is no logical flow of events: he jumps on the creature, disappears from the scene for quite a while, and then the next time we see him, he's off the creature again, even though we never see him fall off. It's all a bit jumbled. I think the least you can do is show him riding out of frame, then later have a short bit with him falling off, getting back on, and then get back to rescue Padme. That way you could still cut the dicey looking stuff, but also keep things logical. It's a nice idea to see him tame the creature with the Force, as the music cue indicates, but again you don't really follow up on it by showing him jump on the creature. In your cut, it feels like he comes out of nowhere when he's riding into the shot to save Padme.
The appearance of the Jedi is a bit too sudden, I think, but the musical cue first very nicely!
The battle in the arena is rather messy, so I don't think you've made it better or worse. I do think you should've kept Padme's part of the quip (unless you cut that earlier in the movie). You have to stay with the characters in a scene like this, and little bits of dialogue help (plus, the OT characters had time to crack wise most of the time during battles as well :P).
We kind of "lose" Mace in the battle. I think it's important to keep him involved in it, since he's a recognizable character. It's a bit more interesting to see him fighting instead of a bunch of name- and faceless extra's.
What happens to Anakin's creature in the battle? We lose him as well.
The original cut of the scene didn't have this either and I don't know if it's possible, but maybe it's an idea to change the music into something more grim when we see more Jedi dying and the remaining ones are being surrounded? It might give the whole scene a bit more weight.
I hope you'll see this as constructive feedback, and I hope it might help!