I don't believe Windows Installer will resolve
%username%.pru to
LogonUser property.
FileName column in
File Table is not of formatted type. If the content of the file remains unchanged, but filename needs to reflect logon user ID, you will probably have to use a Custom Action to copy and rename the file during self-repair. Depending on what you want during uninstallation, you may use MSI table or Custom Action to remove these custom files.