Error while configuring OrientDB's distributed server on EC2.

I'm running two instances of EC2 and have configured OrientDB on both. I wanted to run a distributed database. I tried to configure hazelcast but I'm stuck. This is currently the part of my hazelcast.xml

<join>
          <multicast enabled="false">
          </multicast>
          <tcp-ip enabled="true">
            <member>public-ip-address-of-other-instance:2480</member>
          </tcp-ip>
          <aws enabled="false">
            <access-key>my-access-key</access-key>
            <secret-key>my-secret-key</secret-key>
            <region>ap-southeast-1a</region>
            <security-group-name>launch-wizard-1</security-group-name>
          </aws>
</join>

1. How exactly should I configure if I want to manually set the IP? When I manually set the IP, the way i have above, I get a socket connection refused error. In my security settings of the instance, I have allowed all TCP connections.
2. If I want to use EC2's auto-discovery feature, I set aws-enabled='true', set the others to false. I'm not sure what should I fill up in the access-key and secret-key fields.