It is currently available in Japanese.
Download:
http://www.os2.jp/modules/...
OS2 web site (JP):
http://www.fastwave.gr.jp/diarysrv/...
Ported to OS/2 by Sofiya.
Required SDL Libraries.
"ONScripter is a Free Software implementation of an interpreter for the NScripter videonovel creation utility, under the GPL license.
Based on Simple DirectMedia Layer it runs on many platforms including Linux, Windows, Mac OS and now OS/2."
English Project Web Site:
http://nscripter.insani.org/index.html
Source: OS2.jp