Here you can find free libraries which can help you with development for the X series of games.

Data access

X2 FileDriver301 KB Library for accessing PCK files and catalog files (CATs).
X3 Virtual File System80 KB Works with X2FD. It scan given (game) directory and build list of files. Every file is guaranteed to be from the "latest" catalog. Also solves the BOD/BOB/PBB and TXT/PCK priorities.

NSIS installer

Tools for NSIS installer from Nullsoft.

NSIS X2 Catalog520 KB To make your installer smaller, you can put the files into the installer uncompressed. This will make the NSIS compression much more efficient. You can then compress the files into PCK and create CATs.