Login is a two-step process.
- initiate the account and provide an email address. Validate it with the link in the confirmation email that will be sent to your address. At this point you have an account, and can join this proposal, but you can't vote. You need 50+ reputation points. To get them:
- Go to your Profile, and validate your email address a second time using the button there. Once that's done you'll be able to vote, ask questions, etc