Hmm.
I'm not sure what to say here. This song is definatly is not made for R&B. In fact your lyrics pretty much killed the original melody I thought so much of. Either this, or the fact that I'm not a big fan of R&B at all. The only reason I even found this song was by listening to the original melody. This song and he actual one conflict greatly.
Also, Grim's rapping made my ears start to bleed. No offence buddy.
BUT.
You DID do a pretty good job of making your lyrics match the tone, which made it bearable to listen to all the way through... I'll give you that one. This is actually better than most of the R&B I hear tossed around today. I'd recommend it it was limited to this genre.