I found that the internal options to create pak files don't work 100% so I resorted to designing my own and writing routines myself. There are many ways in which you could do this. Heres a simple way to give you the idea:
1: get all your media, and make it into a rar or zip file.
2: rename the .rar or .zip file to something else, eg .dbr
3: Rename and unzip it from within DB / DBP
4: load your media
5: Rename and recompress / delete the uncompressed files.
I have seen utility dlls for both rar and zip files, and rar source codes are freely available on the net

For extra security you could make the original zip/rar password protected.
Obviously making / designing your own file format / compression techniques would be more secure, but a lot more work