Ok, I know I am going to sound like a complete newbie and I know it's probably been asked before but how do I properly lock my aquatica port? I have the aquatica 5d ii housing and I used the port lock to lock the extension in place. However, when I attach the megadome to the extension, it turns into place but there is no click or anything to tell me it is locked. It is very easy to just rotate it counter-clockwise and remove it. I am not taking it into the water until somebody tells me this is how it works haha. I am terrified to ruin this housing on my first trip. I am taking it into the pool without my camera inside just to get the hang of it for now. But won't even do that until I hear back.