Another reason not to install poser to the program files folder is if you deal with scripts. While you can run scripts from external folders linked into poser, it's not as easy or straight forward on some of them especially if they have multiple calls. Once you install Poser into your program folder, adding anything to it becomes  --- well, put nicely, a headache. I have a bunch of different scripts I've gathered (both paid for and freebies) and it never failed to cause trouble when trying to use them while Poser was installed 'where they said to put it'. I ended up uninstalling and reinstalling with the program in a directory off the root (c:poser X -- where x is my poser version)