I imported my FTM tree to Geni via Gedcom file. Several very odd glitches appeared. My mother, Marjorie Aline Warzeski, is showing up as both my mother and my ex-wife. My father's parents, Frank Stanislaus Warzeski (originally Warszewski) and Bertha Marquardt, are also showing up as a second set of parents. Every attempt to correct these glitches runs up against the notice that proceeding with this action will split the tree. I even found a set of instructions ("How can I update my parents") and followed them through.
A couple of things appeared to have changed since the instructions were posted (2011), but in the end I got the same message about splitting the tree. I was ready to go ahead and split the tree, but couldn't figure out how.