NIF is a popular file format used by 3D games such as Morrowind, Oblivion, Fallout 3, Civilization IV, and many more. The Blender NIF scripts enable you to read and write files that are compatible with these games in Blender.
This release adds support for UV controlled textures (for Morrowind) via the OfsX/Y and SizeX/Y channels in Blender's map input tab.
You can grab the latest version of the scripts here:
https://sourceforge.net/project/showfiles.php?group_id=149157&package_id=166219
For more documentation and help with the scripts, visit the wiki or the forum:
http://niftools.sourceforge.net/wiki/Blender
http://niftools.sourceforge.net/forum