Getting calibre2opds working

Okay, I'm usually not this dense (I blame Christmas).

Using a Mac (10.10)

My Calibre Library (2.74) is currently living in Documents/Calibre

I want to use Dropbox (in combination with updog) to have my library available to me "on the road".

So, my question:

• Do I need to move my library to my updoggy Dropbox folder (/Dropbox/Apps/updog) and then sync the whole she-bang?
• If I move the library to the updoggy folder, do I just turn off DB sync, add new books as required, close Calibre and sync?
• Or, am I missing something and should leave the library where it is, establish the location in calibre2opds and sync to Dropbox?

This is making me feel very dim.

I'd appreciate any pointers :blink: