I bought this one the other day. Haven't had a chance to watch it yet, they're VCDs not DVDs so I have to find someone with a local deck, but the guy who sold it to me either acted in the film or worked on the set "getting metal to build the cyborg."
I should probably add that "Ninja" has become a sort of label here, a miscellaneous piece of media culture that people in Ghana have picked up. It still means what you think it means, the ads for Ninja Home Security have a picture of a guy dressed in a black face mask, but there's also a Ninja Coffee Whiskey, etc. I was at a festival one time where a banner proclaimed the upcoming "Ninja Coffee Whiskey Fiesta Party!"
The whole thing is pretty funny, but I don't mean to make fun, if that strange distinction makes any sense. When I was a kid I used to be into all of these American movies from the 1970's that randomly picked up the idea of a ninja from Japan and pretty much ran with it (see "American Ninja"). There's a James Bond film from the '80s (possibly "You Only Live Twice") where Bond and a gang of ninjas attack the enemy base. There's nothing different about how the word ninja, or any number of other random things like the idea of a killer cyborg, gets picked up in Ghana.
Ghanaian/Nigerian films have their own stock characters, they just aren't well known outside Anglophone West Africa. The most common one, and I'm genuinely not playing this for laughs, is the magical preacher who can supernaturally flash onto the screen (keep in mind budgets are low; you turn off the camera, he steps into the frame, you turn on the camera) and banish evil spirits or prevent something bad from happening. He's not necessarily a character in the film, more of a representation of the power of faith. Everyone understands the scene where a woman tormented by spirits or about to be attacked yells "Jesus!" and, shazam, magical preacher. It's understood in exactly the same way that if you see a red-eyed robot lurching toward the camera it's clearly evil, unstoppable and out to kill the main character.
I find Ghanaian movie culture hilarious, but speaking as a person who just bought a bootleg DVD of Predator 3 and has been known to scream "Get to the chopper!" at people taking too long to get into my car, not any sillier than my own. This is their golden age; when budgets are low, production equipment is accessible, demand for movies is high, and everyone is on a relatively equal playing field.