Yes, I've tried to build the launcher too, but didn't manage it so far.

I received some instructions on how to build it from the original developer:
The launcher is based on wxWidgets:

You need to set up that library on your system.
I think the library itself needs to be built.

The "wx" folder was most likely a symlink to:

I used the following wxWidgets build config:
./configure CXXFLAGS=-ffunction-sections -fdata-sections LDFLAGS=-Wl,--gc-sections --disable-shared --disable-sockets --disable-http --disable-ftp --disable-protocols --disable-sound --disable-tarstream --disable-zipstream --disable-protocol --disable-mediactrl --disable-webview --enable-no_rtti --disable-debug --disable-gif --disable-pcx --disable-tga --disable-iff --disable-svg --without-libpng --without-libtiff

For all the building instructions - I probably used some kind of on-line tutorial, as I didn't saved the commands anywhere. In general, when building such project, you:
1. generate 'configure' script with use of autotools (autoconfig?)
2. run 'configure' script, adjust its options (and dependencies you have installed) until it succeeds
3. run 'make'.
Still, never managed to get it to actually build.

I think including korean in the new version is really easy, as the code is already there for Korean, it's just commented out. As long as it could be build.