I am logged in as the Administrator on Windows XP SP3

1) I downloaded the Google Chrome installer- OK
2) Ran the installer and it downloaded Google Chorme
3) After 1-2 minutes I got an error box saying
    "Installation failed due to unspecified error. If Google Chrome is currently running, please close it and try again"
4) I clicked on the "Show me help for this issue" and got to this page.
5) I deleted the %APPDATA%\Google directory and tried again.
6) I got the same error message.

Note that I do not have an existing copy of Google Chrome onmy computer, I was trying to install it for the first time.
Also
A) why does it install itself into %APPDATA%\Google? Why can't I tell it where to install, like pretty much all other software?
B) Why can;t it download an executable file that we can run on multiple machines, rather than having to download the main program for each machine?

Regards

swdev1