Don't know if it's because I'm particularly clueless, but where should that signed message be posted? I see there are already some results so there must be a way, only it seems well hidden....
I plan to add an option to dump the votes so anyone can verify them. But currently it's not a priority, because only a few people wished to vote. I think that to the end of the year there will be more people who want to take part in voting. Now I am working at creating the system of voting with cold wallets without getting the private keys.
Temporarily you can find signatures here:
http://coinarchy.com/results