Make LG DVX-642H region free

To make the DVD player LG DVX-642H region free, the same trick as for other LG dvd players can be used, as described here: http://multi-region.net/lg_3620
In case that wiki is closed, what you do is you create a DVD with the folder "RMTM0000", with a subfolder "Scarlet", with a file named "kpjc19_1.dvd". (Some suggest the file should be uppercase).
The length of the file should be 0x500004 bytes. The last four bytes (i.e. starting at address 0x50000), should be 008C1717. The rest of the file should be 00. Some versions of this suggest the file can be only four bytes long and contain "17178C00".
Unfortunatelly you can't put this on a USB drive, but a DVD+RW is fine.

Inserting this disc triggers a region test mode which allows you to select any region, including 0 for region free.