Thanks skeettx,
I've thought about taking the gun down, and think you are correct that it may help clean up anything leftover from manufacturing.
I've never taken apart a combination gun to the trigger group, if you can call it that. I am quite comfortable disassembling pistols, bolt guns, AR15's and the like right down to nothing, however I always have had a parts diagram in case things go sideways. I have not been able to find anything like that for the Merkel B4, so I guess the question is what are the odds I will mess something up digging into those internals? From the very few diagrams of break actions that I've seen, it can get a touch complicated inside. Surprise springs are always unwelcome, ha.
On another note, just after I finished writing the first post, the decocking situation resolved itself again, and I can decock again. Based on what I was doing when it resolved, I'm thinking it will either be a "break in" process that will resolve itself permanently, or I will need to open it up and clean the cocking slide and whatever detent is responsible up.