One Key observation

[Prof J]

I received the One Key kit today and the re-keying went pretty quickly.

At time to install the tumblers, I opened up the case for better manipulation - do not open the case.

As I discovered, with the case open the tumbler installed just fine, right up to the last instruction, turning the key to the 12:00 position. Because the case was open, you can not turn the key to the 12:00 position. The open case interferes with the key turn/locking mechanism. You also can not remove the key - it will appear fully stuck.

So either keep the case closed when you put the tumblers in, or close the case fully to complete turning the key to the 12:00 position.