Unfortunately, I have the same problem as you. My 50mm f2 Summicron and 28mm f2.8 Elmarit don't focus to infinity with any of my Leica-R adapters. The 35mm f2 Summicron was almost there, but not quite. As yours, only my 90mm f2 Summicron can focus to infinity. I am not sure why. The infinity focus needs to be adjusted for these lenses, but I don't know how. I have the same problem with Rollei 35mm lenses too. Sorry, I can not help.