If i'm not mistaken it is not really possible to generate a .mrh file out of character already placed in game because the final version is sort of like compiled executable file, compared to the source for this file.
You could probably build yourself an approximation of your character by dragging sliders in the head tool to positions matching where you had them in character creator... other than that it's likely rather hopeless, sorry :<
Any chance we might be able to get either .MRH files or .MOR from characters created in the CC... one day? In other words, would this even be possible?
I ask because I like the simplicity of the CC and because I've created a bunch of characters already ;-). It's kind of addictive.