Correct, simply rename the file from "Innocent Nurses-0.1-pc" to "Innocent Nurses-0.1-pc.zip" and all is well. I guess the uploader had a bad moment or something and simply forgot to check that the file they were uploading had an actual file extension but hopefully the uploader will correct all the d/l links in the OP to correct this error.
As for the game itself, the Engrish is very strong with this one! There's no complicated storyline, it's all fairly straightforward and easy to advance. Sure, it's not awesome but it's also not one of the worst games I've seen so, for some, it might be worth a look. While it may be at the lower end of the scale and there's much room for improvement (not just in spelling and grammar) I found that even with the faults (or maybe despite them) I still kind of enjoyed it for what it is.