Ludarue, you said it was "hard to get back in." My guess is you applied enough force to the lever that the spring moved out of the way of the lever.
I don't like applying force to moving parts. May have to do with being a pilot. Forcing sticky controls to move during pre-flight often masks the fact that a control cable is off a pulley, and may be about to break. So, when things don't move smoothly, I tend to want to find out why that is, or find somebody who can.
That, and I've broken a few things over the years, by applying force when it probably wasn't a good idea...
I'm overseas at the moment, so don't have the manual with me, but I believe it says not to fully remove the lever during takedown.
The guy at the LGS who does maintenance on rental guns also told me not to fully remove the lever, due to the same issue. (He and the shop manager were the guys who got my lever back in, and showed me the piece of spring wire that was blocking it... I think the wire's purpose is probably to retain the lever, there's a small indentation it seemed to fit into when all was in place.)