I see that you did submit a support ticket for this issue, but just in case you missed our response to that message, these steps should resolve the problem:
1. First be sure to set Firefox as your default browser, if it is not already.
2. In Firefox, select Preferences.
3. Scroll down until you see "cbsitt" in the left hand column. Go ahead and click on cbsitt to highlight it.
4. In the right hand column drop down menu, choose "Use TechTracker (default)" if available, and you should be able to download correctly.
CNET TechTracker Support
When I download an upgrade with CNET TechTracker within the Firefox browser I get multiple pages opening and have to quit Firefox to stop them.
Another problem carrying out a download request, a continuous tab line opening showing cbsitt:// . . . .