Hi Razor, I apologize for not having enough time recently to participate despite my promises, but now I have something to share since I am repacking FFXIII series. Looks like ztool is still more reliable choice for now, at least when it comes to zlib. xtool is not detecting/inflating zlib-compressed file from FFXIII at all, it does inflate at deflate :m2 option but even then slightly less than ztool. Ztool on the other hand both zlib(:m1) and deflate(:m2) reliably inflate file, with :m2 even slightly more(but even :m1 inflate 5mb more than xtool :m2). Anyway, here goes screenshots:
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This is with v0.12, I don't know if it was fixed already or not. Anyway hope it help & best regards, if I find more during repacks I will post.
EDIT: Noticed yet another xtool thread. Not sure why there are so many for same tool but whatever, so I tried that version with zlib and rzlib options and it does seem to be working. Although cmd command piping is broken in that version and so doesn't work with lzscan's stdio (aka: "cmd | xtool | cmd").