Is heat necessary to make kefir from RAW MILK....also what kefir grains do you recommend for RAW MILK

Donna Gates says in body ecology diet that raw milk doesn't need to be heated to get the grains to work but this is only said once and never again in the book or website that I can see.

Also I've tried heating my raw milk to 92 and following all the directions and it doesn't always work with the body ecology diet kefir grains.

1. Is it true that raw milk does not need to be heated once the grains are added?

2. What are the best kefir grains out there that AREN'T TOO COMPLICATED and work well with raw milk?

Thanks all!