Counting from the top:
-Minolta 50mm f/1.7 Rokkor attached reversed
-close up filter +4 diopter [not needed]
-reversing ring (Minolta lens or close-up lens thread attached to Canon filter thread)
-Canon 50mm f/1.8

Now, the close up filter really is NOT neccessary *AT ALL*, I was just experimenting to see how it affects the image. Attaching a close up filter doesn't increase the magnigication ratio (just moves the reversed lens further from the other one and thus increases vigneting. The maximum aperture of the Minolta is not big enough to avoid vigneting either. f/1.4 on the topmost lens would be better.