Many foreigners have problems with this sound, and it can be a real nightmare for Asian people in general, except from Cantonese Chinese, Indonesian or Vietnamese. It takes some practice to overcome to problem, and my advice is to practice some drills like the ones shown on this vids: https://www.youtube.com/watch?v=O7oMwO5PVbg https://www.youtube.com/watch?v=gd-nefL-jyQ https://www.youtube.com/watch?v=O7oMwO5PVbg

l don't understand at all what are you asking. Could you use some examples? l'm sure l can help you :)

Hi. Yo creo que la pronunciamos pero ocurre como en inglés, muchos sonidos apenas se oyen pero están ahí. Te recomiendo buscar más en youtube (watch the show " el hormiguero"). En ese programa invitan a muchos españoles y además es un programa divertido. Cheers!

Hi! We do pronounce the RR sound, always. Not only when there is double R, but also when te word starts with an R: Ratón, rápido, reparo, rojo, etc. If others don't do, don't copy them, better follow this very serious on-line lesson https://www.youtube.com/watch?v=P9mMvuRGKY8 Best regards, Alejo.

The r may not always be as dramatic of a roll as your ear is expecting. This depends on the place in the sentence and the sounds that come before and after it. It will, however, always be different than the normal English r. You have to train your ear to hear (and pronounce) the subtle Spanish r sound (as opposed to the more dramatic one you usually hear when rr appears in the middle of the word, or r appears at the beginning of the word). Also, as has been said, there is variation between accents and from speaker to speaker. I hope I've made sense and answered your question.