I am not sure if this will ever be read, but maybe it gives someone a few hints.
Don't know much about GARbro, but your game uses the KiriKiri 2 engine. You know this since there is a "plugin" folder with krmovie.dll and some other .ddl files that are important for KiriKiri. Also, if you inspect your .exe with a Hexeditor you should find this string here:
TVP(kirikiri) for win32
If I remember this correctly, KiriKiri 2 engine offers a few distribution formats: In most cases, you have to pack your ks files and all the other stuff into archive files (XP3 files) and distribute these together with the krkr.exe file. Or, alternatively, you bundle everything together in a standalone .exe file (called PEXP3), hence just one .exe file and no XP3 files. For your game, the second option should be the case.
In the original KiriKiri SDK (not available anymore since many years), there was a tool called krkrrel.exe or something like that you could use to create XP3/PEXP3 files, but I guess the newer KrKrZ should have something similar. If not, just look if you can find a copy of the old SDK.