BTW, if any of the issuers raises a motion, I will vote neither Yes nor No by default. But of course you could contact me if you want to vote for a side.
If you've sold them short you won't be able to vote.
GLBSE should allow voting on less than the full holding for shares held beneficially for others, who may not all vote the same way.
As explained in the OP, the main reason I borrow them is not for shorting. I'm doing market making, so basically I'm both buying and selling at the same time, I borrow them to hedge my risk of holding too much of them and unable to sell at a reasonable price.
This implies that I will hold some of them most of the time.