UPX (v1.25) can reduce the kix32.exe big time. But compressing v4.50rc1 gives an error with the default commandline of UPX. The -force parameter does seem to work without any problems though and reduces kix32.exe from 248kb to 108kb.

Questions is: does anyone have a reason not to use an executable packer like UPX, that is, does anyone know of any problems?