Hi,
the idea is really great, anyone can write an application (actually a plugin) without having to rewrite everything from scratch. Very good. Plenty of potential possibilities, I like it and I would use it. Here is some feedback to ver.0.22-1:

1/ installation - the problem of dependent libs still persits. I had to go to devel to have easy install which resulted in upgrade of other non-necessary pkgs.
2/ maps. Where are they stored? I have huge amount of osm tiles and I dont want to reload everything again. Normaly I would expect the tiles at ~/MyDocs/.maps/OpenStreetMap I, however they seem to occupy /opt or /home/user? Do they? And - is there a switch to block loading them?
3/ zoom: I dont understand how everybody here is able to read so small maps - myself I frequently use n900 navigation in a car and I absolutely MUST have a zoom factor 2x .
Thanks for sharing it.