Make Multiregion

According to the factory manual the region is printed on the back of the unit. If it doesn't say ALL then it can only play discs form the specified region.
I searched high and low for instructions specific to your model to no avail. I did discover, however, that 99% of LG players use the Aiwa 370 instruction for programming. The steps are below:
PLEASE NOTE THAT THIS MAY NOT EVEN WORK AND YOU COULD CORRUPT THE PROGRAMMING IN YOUR PLAYER MAKING IT UNUSABLE. THIS IS NOT HIGHLY LIKELY BUT IT COULD HAPPEN. USE AT YOUR OWN RISK!
++ To program your player for region free (multi region):
1. Press the Pause button on your remote control

2. Using your remote control enter the code 3, 1, 4, 1, 5 and 9 Note: If your unit does not enter the following mode which enables you to enter a region code, repeat steps 1 and 2. You may need to enter these codes in a shorter time span for them to work.

3. Press the 0 button on your remote control for Region free, 1 for Region 1 or 2 for Region 2.

4. Press the Pause button on your remote control

5. Power off your player and wait a few seconds

6. Power on your player

++ To view the firmware version of this player:

1. Press the Setup button on your remote control

2. Select TV Aspect and place the cursor on the 16:9 Wide option

3. Using your remote control enter the code 1, 3, 9, 7, 1, 3 and 9

4. Press the Enter button on your remote control

5. You should now see the version information screen

6. Pressing Setup button on your remote control exits this info screen