yeah - that confused me for a while. i kept reporting it as a bug back in beta.
if i recall correctly, there is "small" bug in paperspace importing that places the entire contents of paperspace into a completely different
storey in archiCAD.
try a few different open options and check the storey info in archiCAD each time . . . sorry i can't be more specific - i'm running on my rather small memory chips at the moment!
[edit]
a quick search gave me this:
http://archicad-talk.graphisoft.com/viewtopic.php?p=26461&highlight=paperspace#26461
[/edit]
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