Installed 1.5, downloaded and attempted to install fh, and I get a patch verification error that reads:

Patch Verification failed: the root directory doesn't exist.

From the details:
Failing with 'The root directory doesn't exit' because: !wsFileName::DirExists(this->root)

I'm running Windows Vista, if that makes any difference.

Edit: May have downloaded the 32 bit version instead of the 64 bit version.  Checking that...

Edit 2: Trying the Bit-Torrent link, they don't specify 32 bit vs 64 bit, so should I be using a different 2.25 download source?

Edit 3:  Ah! Read the Instructions.  I need to download and install FH 2.2 first. 

The link you supply to download BF2 patch 1.5.  Where does that come from?  The latest official EA BF2 patch appears to be 1.41, found http://largedownloads.ea.com/pub/patches/BF2/.

Not that I'm a suspicious SOB, but...well, yes.  I'm a suspicious SOB.