Someone following my Facebook posts commented to me about your thread here, Steve and I thought I'd give my two cents. I pretty certain that Figo Preto and Black Madeira are the same. I have two trees of each that were planted in the orchard in August 2013. My first ripe fruit from them was from one of the Black Madeira followed by a Figo Preto a couple of days later, but I don't think the timing is due to genetics, mostly just by chance. I've eaten a couple of dozen of each and have never noticed any significant difference from one tree to the other, mostly from one fruit from another on the same tree.
One of my Black Madeira trees is grafted on Black Mission and that tree is substantially larger than the others and, because of that, produces more fruit, but the timing and taste is the same, IMO. Perhaps, if I thinned fruit from it, I could get ripe fruit sooner because of the increased vigor of that tree.
I am also growing one of Keith's black fig from Madeira but it is a young tree still in a pot. Based on the leaves and the fruit photos he has previously shown, I believe it is mostly likely the same. I also hope to compare to Francisco's Violeta one of these days.