I found something on a Chinese forum:
http://www.tsdm.me/forum.php?mod=viewthread&tid=873428
It shares both MP3 and FLAC versions. Unfortunately, the FLAC version is only available to certain members, and the forum is in Chinese.
But good news! There is a way to access the Hi-Res FLAC versions: donate via PayPal.
Details here:
http://www.tsdm.me/forum.php?mod=viewthread&tid=756436
I'd do it myself, but I don't have any funds to spare at the moment.
So if anyone could donate their way to the Hi-Res sections of the forum and grab the FLAC version of the soundtrack, it'd be very much appreciated.
EDIT: So I checked the MP3 download link, and it's on Baidu. Chances are, the FLAC download link is on Baidu as well.
The problem with that is that Baidu downloads tend to be slow at times, and besides, there is a limit to the size of the file you can download on your browser. I don't remember the exact limit, but I'm guessing that anything that's at least 2 GB will have to be downloaded using Baidu's cloud browser, which is in Chinese.
If someone can find a way to get past all that, it'd be very much appreciated.