Your client is not "extremely gun-shy"....he has every reason to be afraid of theft of his items.  Anything that gets put up on the net is up for grabs.  It's just a question of how difficult you want to make it.
Anything that is compiled can be de-compiled.....I'm sure a 16 year old kid would be able to crack your flash files.
If you do music and video, be sure to just include short clips so that the entire segment cannot be stolen.  If you do images, make them as small as possible and watermark them.  As for text.....don't think there is much you can do to safeguard......

In youth, we learn....with age, we understand.