For Long RCs, generally I read the 1st question and then read the entire paragraph focussing on this question. This way, I quickly run over other texts just knowing what each paragraph is about and how it relates to the entire passage. Later on I revisit to specific portions.
For short and complex RCs, I try to understand the paragraph well in the 1st go , so that I do not have to revisit.
I am yet to encounter long and complex RCs, thanks to my poor reasoning skills in CR.
Detail questions generally appear in Long Passages. I use the trick by Kaplan - find the key word in the passage, read the sentence along with the preceding and succeeding sentences. Since you are looking for quick fix way, this may not give you 100% accuracy.
For Inference questions, I do not think you can do it in quick fix way. You need to understand the whole passage and view points, relate them, and come up with a approximate idea that matches with one of the answer choices.