From Dragon Age Toolset Wiki
DAZIP files are packages of exported resources ready to be installed and loaded into the Dragon Age game. The format is actually just a renamed ZIP file, and can be opened by any zip editor to manually extract or manipulate the contents.
Inside are the exported binary resources for a module, packaged into ERFs and arranged in a directory tree corresponding to where they will be placed when installed. Also included is a manifest XML file that contains information about the module, such as title, release date, version number, and so forth.
See builder to player for information on how to generate a DAZIP from the toolset.
To install a DAZIP so that your game can use it, either double-click on it (if the file type has been associated with the DAUpdater program) or go to the bin_ship directory where your game executable is and run DAUpdater.exe manually.