I'm not able to use PFM for a few reasons, but I was able to find an unpacking utility. I'm trying to re-size a few textures to see if that will increase my battle performance, anyway, just wanted to know if I have to create a new .pack file or if I can simply delete (or rename) the original pack and simply copy the folders and sub-folders with my changes into the data directory.

Probably a stupid question but I thought it'd be worth clarifying on the board at least.