I don't have a bypass code but I just got the VM8023HD and I bypassed the safety feature by simply attaching the pink wire to ground.
You can do so by wrapping it around a screw on the metal frame or by attaching it to the same wire you attached your black wire to.
Now hopefully someone can help me with a question I have. The jlink cable I got with the vm8023hd works for my wifes old 2nd gen nano, but not for my 4th gen. I believe what they supplied me with is the first gen jlink cable and not the jlink 2. However compatability for the 1st gen jlink is said to include the 4th gen nano, but my stereo doesn't deteched my 4th gen when I plug it in.
Has anyone had this same problem? I don't want to purchase the jlink 2 cable just to find out that it doesn't work either, or that the jlink 2 is the one I have.