I agree with Gaspine thought, you have a to use a Sqlite3 driver to open Calibre's database.
What OS are you using ? from the directory you typed it doesn't appear to be any variant of Debian or Arch.
Have you restarted your php fastcgi after installing sqlite package ?
Sorry for the lost hours
I'll add a warning in next release (should be later today).
About your other question about a web browsable catalog, I'm currently coding it, I'll post a link to my work in progress later.