Interesting site. Ran across it because someone had inquired at a UK site about using molasses to relieve RLS, so I did a search and this forum came up in the results. Because this is a site centered on finding natural relief, I am assuming most people here probably don't use much in the way of prescription meds, but I thought I'd throw in my 2 cents' worth - cholesterol lowering meds are so widely prescribed now, people need to know that they trigger RLS as do a lot of other meds.
Now for what has helped me immeasurably - when I realized that lower back trouble triggers RLS in me, I invested in an inversion table that I try to use every night. It has done wonders for me. As my back goes, so goes RLS. And I have found that lower back exercises also will calm it down, specifically the "bridge", and the "bird dog". You can do an internet search for those with the word "exercise" and find them pretty easily if you want to give them a try.