I just tested it -- and it seems that this game is in French without the option to change the language to English, so I don't understand what's going on at all. But what I did see, that instead of
*.rpa files it has a couple of
*.jas files in its game directory, which I wasn't able to unpack/decrypt to check their content.
If you just add the
0x52_URM.rpa file to the games directory, URM won't work (I guess because the game is expecting
*.jas files instead of
*.rpa...?! That's just a wild guess on my end though), but if you extract the
0x52_URM.rpa with unren, URM works just perfect with this game
// EDIT: Looking at the file
renpy\loader.py in the game's directory, I can confirm that it's only accepting
*.jas files:
...and if you rename
0x52_URM.rpa to
0x52_URM.jas, URM works perfercly fine. So no need to unpack URM, just rename the file