Taking some OSM (*.osm) data downloaded from Geofabrik I have created a Spatialite database using spatialite_osm_map. Now I have problems, because some of the data that is supposed to be in the form of polygons appears in the database as polylines, which I can't style properly. As an example, objects tagged "natural=wood" appear correctly as polygons in the DB while objects tagged "landuse=forest" appear as lines.
I think this must be something to do with what I've seen called the "multipolygon problem". At present I am loading the affected objects into QGIS, exporting them as shapefiles and then polygonising these, but there must be a better way of working. Any help on this topic would be gratefully received.
I ought to mention that what I know about Spatialite and OSM data wouldn't fill a thimble.
Added later: here is a screenshot illustrating the problem. The "polygon" selected by the info tool is in fact a polyline. Nick.