I can relate in a sense. When Sonar went to the X series UI  (Skylight) after Sonar 8.5, I was totally lost. However, over the years the UI became more and more familiar to me.  In fact, I am still learning about features that were introduced after Sonar 8.5. I think you are at a major disadvantage since you never migrated to the X series (Sonar X1 and successors) after Sonar 4.  In my personal experience, Cakewalk by Bandlab greatly improves upon the pre-X series, though I do miss a couple