See the text in the top left? There should be more text than that, meaning it didn't load correctly. I thought my computer was still on Japanese regional format, but for some reason it wasn't (probably cause I forgot I changed it some time ago and all the games I've played since have just worked until now). You need to make sure the regional format on your computer is set to Japanese.
LocaleEmulator doesn't work on this game whatsoever sadly, even if you force open it with something like Easy Context Menu.
View attachment 3603122
Notice the line of text in green. (Also about the font, I tried to use the font Mtool recommends, since it's thinner, to try and solve the problem with the text overlapping, but it's only working okayish.)