Hi lizet,
Yes, I believe you can obtain a refund, if it hasn't started processing yet. It takes a little while to receive the refund, but you'll get it. You could call CIC and ask about cancelling.
When you apply inland, you waive the right to appeal, if they reject you. I'm not sure why. It would be more fair to allow appeals for inland AND outland, in my opinion.
There's no guarantee outland would approve it either, but you'll know whether it's approved/denied faster (a matter of months), and if they deny you, you can appeal whatever problem they raise. I don't believe they can deny you twice (similar to double-jeopardy), so if you win the appeal, you're good to go. As long as your situation/application doesn't have anything obvious which would raise suspicion, you should be fine, or at most, be called for an interview, if you lack supporting evidence, etc. I can't tell you for sure what will happen with your case, but if it's straightforward, you should be good.
I'd definitely go outland, if possible. It's faster, you have the right of appeal, you can come and go from Canada as you wish (provided you prove you won't overstay your allowed limit (visa-exempt is six months)), etc.