but if in one pose inside the lot someone renamed the PoserSurface node you may got an extra PoserSurface node.<<<

That might be the problem, then ... I've seen nodes renamed, but the main issue here is that the Poser Surface Node was renamed as well, which as far as I know isn't possible within Poser itself because the Poser Surface Nodes are named that way by default.

So it seems to me that the "bug" is in the pose files, and not Poser.