Uninstall UR first, or use the /DIR command-line parameter when calling the installer. If a previous installation is found, it defaults to that location and does not prompt (UR uses Inno Setup for its installer, and this is the default behavior for Inno, so I suspect quite a few installers work this way these days).
http://www.jrsoftware.org/ishelp/top...ususerinfo.htm
http://www.jrsoftware.org/ishelp/topic_setupcmdline.htm