md5 files don't start being part of the modding process until chapter 2 when you are preparing to install the various .wad files.
Sounds like that you don't have the Hackmii Installer on the card. If you are following the Softmod Any Wii guide, you are told to uncheck the "bundle hackmii installer" (which sounds like you did, otherwise you would get it from letterbomb), but then you didn't do step 4 of the "letterbomb spoiler" that says to download the "hackmii_1.1.0.zip" file and extract it to the SD card's root directory.
3. Uncheck the "Bundle the Hackmii Installer for me!" box.
You can use the mac address to build a custom hackmii installer at LetterBomb
MAKE SURE YOU SELECT YOUR REGION up top
If you get the captcha wrong, it will RESET your region. This happened to me. If you do, the installer, well,
in my case hung the wii. Had to hard boot it.
4. Copy downloaded files to root directory of SD card. I used windows xp. Now download hackmii_1.1.0.zip and extract the boot.elf file directly to the root of your SD card.