Could someone help me?
Can I install the wallet on windows 8?
It seems not working..

Downloaded Sia-UI-v1.0.3-win32-x64.zip
I conform i have windows 8 win32
The UI that you downloaded is the full app, which includes a wallet. If you don't plan on storing files or starting a contract, why not use Poloniex as a simple wallet service?
what the ....
do
NOT recommend using Exchanges as Wallets !
maybe you were not around but heard stories about Mt Gox, MintPal ,.... eh ? think about it !
Do NOT trust exchanges, they are there to trade but NOT to hold/store your coins.
problems with wallet ?
check in on slack - they will sort u out