Either I did something wrong when I first got it, or I got one that isn't working as it should. I could not get it to unlock. I tried turning the drip tip (pushing in, getting it lined up with the grooves) and then pulled it off and turned the stem thing every which way and nothing. After I got desperate, I pulled the center stem out entirely and it finally got juice to the coil, but flooded. I put the stem back in, and I still can't get it to unlock. I ended up rotating the white plastic thing at the bottom to open the holes feeding the coil. It works great now, and holy cow on the taste, but I don't think I did anything right and I'm worried I may have messed it up.
After this tank is empty, I'm going to take it all apart and see if I can figure it out. Maybe the inner stem isn't connected where it should be? Maybe I'm not even turning the right thing? I don't know. It's been a long time since I felt like a vaping newb.
*eta*
I don't want my post to make others wary of trying out this glassomizer. I can't say enough about the flavor from this thing. The best vape I've ever experienced, hands down. Crazy amount of vapor, no burning of the juice at all (had issues on the Nova for some reason with this juice), just insanely good. If I can't get the lock feature to work, I really don't mind. Biggest problem I have is that I'm incredibly clumsy and I don't know how long this glass tank will last considering my history of dropping PVs.