I think you went the wrong way around, 1. Backup your Poser 6 Runtime. So you have a copy to restore to if something goes wrong. 2. Copy your Poser 7 Runtime into your Poser 6 Runtime. On the Mac ditto it in. This will overwrite all the old Poser 6 Runtime Files with the new updated Poser 7 Files if they have the same name. 3. Rename Poser 7 Runtime, something like Runtime7Fresh. So you have a copy to restore to if something goes wrong. 4, Rename the merged Poser 6/7 Runtime to Runtime. This worked for me.