Thank you for this, l had no idea that the middle part (which you circled in red) was meant to flex ever so flightly, that would explain why it's independent of the areas either side of it - l thought it was a past repair job. Well, my quick fix with glue more or less prevents the middle part moving now, l think l used too much glue. The glue was actually a flexible glue, but given the quantity l used (in anticipation of the part coming loose, which it did once during the repair process), the area has now frozen stiff. As l say, l think l might finish with sandpaper or something. The camera works anyway and as you say it doesn't seem like a huge deal, it just hurts the ego a little bit, to be affected by this tiny part.
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