Currently not, but when some map-renderer gets integrated into modRana, the per-country files from Cloudmade can come handy.
They provide per-country POI databases - this could be integrated near-term to provide offline-poi search.
And there are also some Cloudmade provided (tiled) map layers, which could be added.
Concerning adding new map layers, I really have to improve map layer switching. The current toggle method is IMHO no longer suitable for so many layers

You mean like converting OSM to SVG by some XSLT magic and then displaying it ?
BTW, try Inkscape, its a vector graphics editor with good SVG support.

Development update
I'm currently doing the POI functionality rework. The database structure should be Mappero compatible, but modRana will use its own database file by default. Like this, users should not mess up their potentially extensive POI database from Mappero without explicitly enabling it in options.
I'd also add automatic import from the old non-db storage.