I have done two batches of coffee soap successfully. Perhaps I may be able to help here. Before you make this, freeze the brewed coffee. That is why it stunk. probably got some bubble action too huh?
You do want to double brew. Could even try triple or quadruple if you so wished. Anyways, you want to make ice cubes from the brewed coffee. Once they are frozen, then add lye to it small amounts at a time and stir. The lye will melt the cubes and not "fry" your coffee.
I have not heard of the cream thing, at least not at trace, so I cant comment much on that. You did add the grounds in right though.
An FYI. I can tell you that the coffee grounds are VERY abrasive. I would not use on delicate skin or sensitive areas.
If you or someone you know has thick skin, it might be OK. I will be cutting my up smaller now to use as hand soap. Would work great for dirty grimy hands.
Tip: I have noticed that most of the time when ever replacing any liquid to be in place of the water, 9 times out of 10 (if not all the time) should be frozen before hand to avoid the lye from ruining that liquid, Whether it be tea, milk of sorts, coffee, etc. May not be a bad practice to do anyways, if its not water that is. This way just seems like a "safe" rout.