This issue pops up from time to time. As far as the receiving the portion of your withdraw. Why this happens is as folks continue to mine and deposit very small inputs say 5 coins over and over again we build up a ton of small inputs. When say a bigger trader comes along and make one large withdraw. All of the tiny inputs have to be combined to make the large withdraw of say a million so that could be 200,000 inputs for that one transaction. Whats this do it typically hangs the wallet so we implemented a "fix" that will keep making your withdraw smaller until it sends. We also then get alerted and work on combining inputs internally so that we do not have the problem in the future (this takes a bit).