I get the following message from something called reg: https://imgur.com/a/fieO6TX
In text: オリジナルディスクを入れて下さい
What I've done:
> Got the game (MDF file)
> Used WinCDEmu to open it
> Installed it
> Launch it with Japanese Locale Emulator https://xupefei.github.io/Locale-Emulator/
Since this is an old game, I couldn't find any info. I found something related to Rewrite but the fix seemed to be game specific / required a crack.
So yeah, currently somewhat lost.