Gopher, our Surinam RTB was raised on live rats and had a scabbed over hit from one to prove it. As a challenge, we bought him anway.
After about 2 weeks to let him settle in I did the first feeding attempt with an FT rat and warmed it also with a hair dryer. The room was dark also. He seemed interested, but unsure. Soooo, I left the rat draped over his climbing branch and headed off to the pet shop to get a live rat...just in case. By the time I got back home - viola! He had ate it.
The second feeding was done the same way. By the third the room was dimly lit and he also took that one. Of course now, he takes 'em any ol' time! My reasoning to have the room darkened was to have him rely more on smell and heat signature and limit as much as I could the sight aspect of it. Anyways - he bought it!
It just takes a lot of patience and the longer he/she goes the more hungry it will get which will play in your favor.
So far as an RI - what Patrick said above.
And as tank size goes, my rule of thumb is for every foot of snake, 1 square foot of tank area.
Oh yeah, RTB's need belly heat in order to aid in digestion. For whatever wierd reason as compared to other snakes, they seem to have a rather sensative digestive track which means you will have to get an UTH. Keep in mind heat travels up, not down. Gopher has 2 in his tank - both low wattage as he likes to borrow under the substrate. If he doesn't get under the substrate after eating - guaranteed 100% of time - on the third day he will regurge his rat.
Yes it's disgusting, but trust me, the smell is 10 times worse than it looks.
Patience is a virtue. If all of your other variables are "dead on" remember...you are dealing with a creature that has the brain approximately the size of a chick-pea. Out smart it.