First, there's no "DI shard offline mode". The Deep Island Server (or shard) is made for playing online; you can already play URU locally on your PC (offline). So using a server for playing offline makes no sense. If you meant to access Deep Island content while playing offline: that's not possible as well.
But I assume you're referring to the extended capabilities you get when playing on DI.
If you're interested in the extended KI commands, then the
Offline KI might be something for you.
If you want to get fan-made ages in you local game installation as well, eventually
Drizzle is what you're looking for (which can install the Offline KI for you automatically as well).