I just bought a mix and I found out two zones on the mix can't be unlocked unless you connect it to another mix. I convinced my friend to buy one, so we will have two mix, but I know I won't get anyone else to buy them (we're in our mid 30s, so none of our peers are going to be interested. Lol ) can we unlock the zones connecting our mix's to each other? Or does it have to be three unique mix's?