I was having trouble getting PD 4.0 Home Edition to install on Win 8.1: the installer would crash. It doesn't want to install from the CD no matter what I tried. If you have PD installed on a windows 7 or XP machine, clone the PD folder in program files(x86)/Adobe/ to the windows 8 machine in the same location. Copy the contents of the installation CD to a flash drive. On the flash drive, locate in (preferred language folder) setup.exe and set compatibility to "Windows XP service pack 3" and "run as administrator", then double click that file to install. Before rebooting go back into your installation folder in Program Files(x86) and change compatibility of PD4.exe to: "Windows XP SP3", check both "disable display scaling" and "run as administrator". I don't experience the explorer hang issue - it starts/runs just fine with a minor cosmetic UI issues here and there.