FWIW. I did a clean install of XP SP3 on my laptop. Previously I had MCE on it and could not download a config file to my 9800. I just sucessfully downloaded the file to the 9800. The only HID I have installed other than the 9800 is a kensington trackball with its mouseworks software. I had the same device attached the laptop with MCE when the downloads to the 9800 failed.

What a relief but I still don't understand why it works now and didn't before given that people here have stated they got it to work on pretty much all the various Windows OSs......