It has worked fine for about a week until it appeared all blank today. Sometimes it's back to normal for a brief moment, usually when i click 1-2-3 times it goes blank again.
I think I downloaded it from here https://github.com/ethereum/mist/releases
What worries me is that I have read on different Ethereum related sites that there has not been made a safe/proper wallet/client yet. But i don't intend to store the wallet files on my computer, I'm going to get a certain amount of Ether and then store all the files on several external harddrives not connected to anything.
Which brings up another question... is there any way in that scenario I can lose the Ethers? Is there possible bugs in the clients today which could simply make the Ethers stored just disappear, or be impossible to extract from the wallet in the future?