How can I easily convert OSM to MBtiles with default styles?
I want to do a really simple thing:
1. download city data from http://metro.teczno.com/
2. **do some magic (where I don't have to write bazillion stylesheets by hand) to convert it to MBTiles**
3. run it on a mobile app offline
The problem is that I can't find a way to sensibly convert the data. I've tried Tilemill (trust me I really tried), but it just doesn't do what I expect. It doesn't really care if I add layers, most of the time it just errors or does nothing for 20 minutes, and even when I get it working the best I could do is this

I don't want anything custom, I don't want to create my own layer thingies with custom graphics, or customize how the map works. **All I want is to take the default look of OSM, slice a region and stick it into a MBTiles format.** I also tried [osm2pgsql according to Tilemill guide](http://www.mapbox.com/tilemill/docs/guides/osm-bright-mac-quickstart/), but Tilemill crashed saying that there is some invalid data.
I've read tons of documentation but everything just refers to one more complicated tool than another and 1000 ways to customize things. I tried mapnik and mb-util (which tells me `file is encrypted or is not a database` for every single file format I've tried), but I couldn't find a simple way to do this.
**Could someone please point me to a resource or explain a simple way to take `.osm` and shove it into a `.MBTiles`?**