I have a fairly big dog, but posted this on a thread recently to give an idea of the percentages I have been feeding. If you VM Sleeping Lion she has a lot of knowledge and I believe will send people copies of her feeding guide (sorry SL if that is inaccurate!!):
Not sure how helpful this will be but it may give you some ideas. I started feeding Kilo raw at 71/2 months and the quantities I fed are:
7.5 months 35.5kg 1.4kg raw 3.9% of total bodyweight
8.5 months 39.5kg 1.3kg raw 3.3% of total bodyweight
9.5 months 41.5kg 1.2kg raw 2.9% of total bodyweight
Looking at the graph I have kept (I know - what a geek

) I would expect him to weigh around 46 - 48kg at 12 months but not sure about adult weight as RRs are slow to mature apparently.
I tend to feed by eye and have been decreasing the amounts as Kilo's growth slows. He was difficult to keep weight on until about 8 months when I could finally catch up with him.
Here is was at 8 months - I think he looks about right:
Hope that made some sense and that someone knowledgeable comes along for you soon

.