You're going to need WadManager on your SD Card in the apps folder.. I ignore the update prompts from HBC..
Throw the Neogamma .wad onto your SD card, run HBC..
Boot WadManager.. Select SD card, rather than USB..
select the wad and hit the + button, it'll ask you to confirm the install.. confirm it..
Sit back and relax. Hit A at the end to restart the Wii and you should be golden. Hope I helped. Good luck.