You have to keep on playing and playing until near the end and then start loking for the key. You are able to pick it up and the moderators will say they have added it to your inventory and then you got to the Hidden lake and unlock the door. It is great fun in there!
You have to land on the little islands.
You have to play black puffle rescue but you have to be a member
You need to be a member and play the puffle rescue game and it has to be the black puffle. you need to complete the black puffle rescue game and you will receive the key. In order to use the key you need to be a member. This worked for me and I hope it works for you :-)
You will get the key when you have rescued the black puffle in puffle rescue three times it does not work
go on puffle rescue on the black puffle and follow the squid
at the black puffle rescue at the mine
There will be a hot pink puffle on CP this year, 2011.
On the black puffle rescue get the puffle and wait there until you see a squid shadow and then follow it but keep walking into the bubbles so you don't sink and then the shadow will lead you into a secret place and find the key! that's all
Are you talking about to get the hidden room in the under ground mine? Well, you'd have to go to the puffle rescue game, be a member, and click the level with the black puffle. You pass the level, i belive, you get the key immediatly. Im not a member so im not sure how you get the key dead on, but i know that much. I'm Wowhoa or Wayss on CP. Hope i meet you some time! -Wowhoa and Wayss on cp
Its in black puffle rescue near the end
if you follow the giant squid shadow and jump on the bubbles behind it in the first level of the black puffle rescue you get the key to the underwater member room
you play puffle rescue on black and follow the octopus shadow [get bubbles for air]