Encoding format of Japanese NLF

Can someone share what format the NLF files are encoded in? Especially Japanese.

Then can someone share how I would go about getting my own Japanese text into this format?

In their native ANSI codepage. For Japanese it's 932.

Allright, so I can get the encoding setup correctly.

Now of course, is there a means of changing the code page used for a particular dialog?

No. The codepage is set by the system.