This was a very difficult translation, not because of the length of it, but because the low resolution of the images and the use of complex Kanji made it difficult to read some pages (particularly the diaries at the end) properly, never mind the written text. I did my best.
This story was originally published in chapters in COMIC Zero-Shiki, but only a few issues are available.
You did a good job! I think some people are giving low ratings and tagging "rough translation" on galleries regardless of the actual quality of the art or translation.