Macs replace the directory with the new one that you are copying, loosing everything in it, while windows merges the two directories and only replacing the files. I lost a few runtimes on the mac because I did not realize this. I have been using crossover office and an explorer replacement utility to simulate the windows version of copy, that or Fusion and start up windows to do my installs. Crossover does not require windows to run but I have not found a good enough utility to use as an explorer replacement and allowing me to view inside of zip files instead of decompressing them. Fusion runs great giving me Windows but you have to wait for windows to start and it slows things down a bit. I will have to find this ditto program and give it a shot. I use a macbook pro for Poser, Vue, and the daz programs mostly. I have to start up windows in Fusion to run clothing converter and tailor with a version of poser installed on it and it works fine.