How to include MacOS X preferences files and app preferences files in InstaDMG builds

Hi, I'm wondering how you go about including preferences files for MacOS X and preferences files specific apps in your InstaDMG builds. The way I currently do it is by packaging a user template with all the users' preferences files (both for MacOS X and for general apps). This way all of the preferences files get put into the ~/Library/Preferences/ folder for every user who's created. And for the non-user specific preferences files (the ones in VolumeName/Library/Preferences/) I also create a package that installs them. However I've had many problems with this, including the following: • The Airport performance on imaged machines is terrible (need to use an Ethernet cable for it to be useful). • When booting up machines they don't automatically join known networks, if the networks are password protected — even though they have the correct password stored in the keychain. The Airport Select Network dialog appears, but the user has to double-click the network to join it. And the password is already filled in when the user clicks on the network — the Mac just doesn't want to join it automatically. Pretty weird. • Also stability is not that good and much more. I'm curious, is there a better way of doing it? For instance, I'm wondering if many of the preferences settings could be set by issueing defaults write commands.