How to select addr to vote when wallet have two addr。
I'm researching that, too.
It's tricky with QT wallets - Seraphim helped me to find out new wallets are always assigned a default address when they're created, and that's the "send" address. Any others are basically just "receive" addresses. You'd have to use two separate wallet.dat files. E.g., usb sticks or keep renaming / backing up .dat files...
Not sure I'd recommend it for most people, but a web wallet could probably manage to track that stuff.
You may be able to do some stuff by "sweeping out" all coins from the addresses from wallet 1. These may be split among multiple addresses. Send the total balance in wallet 1 to any address in an empty wallet 2. If you vote from wallet 2, not quite sure if the vote would show as the address you sent to or the default wallet 2 address. But, it's a start...
If anyone finds out more, let us know.