(back to the repossessed house again)
A couple of the doors need the multipoint locks engaging to stay shut, and on looking at it a little closer, there appears to be a plate that can be clamped onto another in the centre latch keep that will allow the door to be closed without engaging the multipoint locks (hard to describe unfortunately, but a very simple "device" in practice) - it just provides a ledge for the latch to "latch" behind.
Not sure how this will come out in ascii, but to hell with it :-}
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