POF files DON'T have textures IN them, just association data.
All textures for Retail or SCP are in VP's or the Maps folder.
You need to be more specific, cause if you DL'ed someone's single modded ship they should have added the maps in a map folder, or all files in one big folder and you have to sort it.
OR... The maker is using textures they assume you already have from previous or other downloads (like a texture pack, Retail, SCP, or a previous ship with a texture set they reuse.)...
So what's the problem? (in detail).
[EDIT] I had to reread, I almost reposted what I just told you 2 posts ago...

Things would go a lot faster for you if you recruited someone from the community.