hi,
there is no such thing as 'original shapes' in osm street data, since the street data only consists on attributed lines.
CityEngine creates the shapes dynamically based on the data available. the issue is that sometimes the input is already not so good, there we cannot do anything. [ osm is free data .. ]
but we've been working on the importers and cleanup tools a lot, so they should do a much better job in 2013.
ok ?