The game is no longer available as the download links for it were deleted.
In 2007, the official site contained a QR code to download the game, but when scanned, the site it leads to doesn't work anymore. It seems to lead to a RPG Tool site, most likely how the game was made.
Corpse Party: NewChapter didn't contain chapter 5, as it was ported to the PC before the release of the chapter, leaving the mobile version discontinued.
The character portraits for Corpse Party: NewChapter were noticeably different from the PC version's, where they were slightly improved.