The XMP Toolkit SDK needs zlib.
This release uses zlib Version 1.2.8
To get zlib:
1. Obtain a copy of the zlib source code (not the compiled dll)
from http://www.zlib.net/
(download links at the time of writing were at the bottom)
2. Place all top-level .c and .h files of the tar/zip you downloaded
directly in .../third-party/zlib