There's actually nothing wrong with the file. It's just that for whatever reason, Windows 10 wouldn't mount the file correctly, and Virtual CloneDrive would only mount it as an audio file. What actually DOES work for this is Daemon Tools, but since the Windows 10 version for that is kind of eh....you either have to use the new Daemon and bear with the malware, or use an older version of Daemon Tools on an older version of Windows.
Or do what I did and make a Windows XP machine+older version of Daemon Tools to mount it on. Or!
https://mega.nz/#!igxk1QxC!lBN_FjKr-sL8 ... NabuT6L250Download this extracted version I made, and play from there. It was made from a Windows XP install, with Japanese locale on. Should be clean virus-wise, since I made a new virtual machine just for this.
Mount the .ccd file you downloaded from the site for ingame music, and then click on 月姫.exe
All the other discs in TsukiBako works fine, so this is just that version of Tsukihime.
It's not a real replacement for a disc image that'll read natively in modern Windows, but it'll do in a pinch. I tested this on my Windows 10 Pro.
(I've tried using Daemon Tools to convert it to mdf/mds, but it still wouldn't open in Virtual CloneDrive when I try it.)