Build 30 can be downloaded from here:
This is beta version! It has not been tested.
The offline copy feature in the network calendars requires some additional testing still. I suggest that you make a backup of your events (also on the server) before you enable it from Options->Calendars.
You should also note that even if you are able to add and modify events while off-line it's not possible to delete the them without the network connection. Or well, you can delete an event but it will appear again when the connection is available and the event is read back from the online version.
The list of changes:
[2.0.1 Build 30] - 10 Dec 2006
o Alarm sound set for an event was not played. Fixed.
o Added "Keep offline copy" option to network calendar.
o Fixed a hang when a recurring task was set to completed.
o Pre and post days were shown always in the Dec-Jan. Fixed.
o The Private-checkbox didn't work. Fixed.
o Tooltips shouldn't pop up anymore if the menu is open.
o Improvements to the legacy skin support.