It sounds like you may already have looked at this FAQ article, but if not, and if this is still an issue for you, please do check it out and follow the steps therein:
Specifically, you may need to enable hidden folders in order to see and select the appropriate options.
However, if you have done all of that and were still unable to resolve the issue, your best bet may be to try a "clean install" by following these instructions:
1. Completely uninstall TechTracker from your machine. If you need help with that, please see this page:
2. Clear your default browser's cache and cookies (at least all of those pertaining to the following domains: cnet.com, com.com, and download.com).
3. Completely exit/close out of all running instances of that browser.
4. Remove the registry entries for TechTracker from your computer by running this command (but please be very careful to only run this specific command, as making unwanted changes to your registry can cause serious problems on your machine; you may want to backup your machine beforehand just in case):
REG DELETE "HKCU\Software\CBS Interactive" /f
(Please note that if you do not see the "Run" command option in your Windows start menu, you can access it by pressing the Windows logo key on your keyboard and, while still holding down the Windows logo key, pressing the R key as well.)
5. Re-start your machine.
6. Open your browser and download TechTracker again:
7. Once you have re-installed TechTracker, run another scan and click the "Get Updates" button to go to your CNET TechTracker page. You should then be able to complete the steps in the aforementioned FAQ article, if necessary, and download updates normally.
CNET TechTracker Support
I am using the latest version of TechTracker, and Firefox 13.0.1. I discovered that this file type was not listed when I attempted unsuccessfully to download a file from my Updates list. Replies to similar problems on this Forum indicate that in order to do that in Firefox, it is first necessary to set TechTracker as the default program to open CBSITT data types. My first action was to reinstall TechTracker. That did not change the situation