After having a bit of fun in OS 9 I decided to eventually return to OSX.

Try rebooting whilst holding down the Command + Option keys so you can rebuild the desktop file. This should be done after installing & also periodically. Hopefully this will set things straight for the installer. Otherwise use Disk First Aid to check your system over. Then try again.

The steps in the installation process are in the image below. Where are you getting stuck at? The installed folder is shown in the 2nd image.