Answer Found
I tried everything that was suggested to no avail but have now found the simple and complete answer.
PROBLEM: Belkin Network USB Hub F5L009 gives an error message when you instal the software if you have Snow Leopard "SXUPTP driver has not been installed".
SOLUTION:
1. Download "SX Virtual link for Mac" V3.3.0 (Date 11/13/2009) from
http://www.silexamerica.com/support/software/svl.html
2. You will have downloaded a zip file called "sx-virtual_link_mac_330.zip"; unzipping this will give you a folder named "s-42a330".
3. Within that folder, navigate to SXVirtualLink>contained_packages>Driver>10.6 (the 10.6 refers to Snow Leopard OS); inside there is a file called "Silex_kext" dated 5/11/2009
4. Drag this file into the installation folder Utility>Connect>contained_packages; it will ask if you want to replace the older version of this file that exists there. Click "yes".
Now you can go through the normal installation process as per the manual, and hey presto, everything works magically!!
[If for some reason you don't have the installation disk to start with, or have a problem sticking it on your desktop, it is available at
http://en-us-support.belkin.com/app/answers/detail/a_id/511/related/1/kw/network usb hub/r_id/166 as F5L009 Driver - Mac (version 1.5.0, OS compatibility : Mac OS 10.5; note there is no 10.6 compatible version - and THAT is the core of the problem with the installation disk in the first place).
QUESTION: I know nothing about what the hell I am doing, and yet managed to figure this out from Googling and reading - why can't the brains at Belkin have done the same - it is a trivial exercise for them to have made a version 1.6.0 compatible with Snow Leopard. I am seriously unimpressed!