Welcome to the forums! Just a couple of questions:
You mentioned that you got it to work with Windows 8 when you first purchased the BU-353. Did you test it with the GPSInfo program? Also, did you test it with other programs?
Did you encounter any issues while you're testing the device and the programs?
Have you tried restarting your computer?
How about plugging in the device directly to another USB port?
Also, when you tried downloading various driver, have you ever uninstalled any of them?
If so, did you uninstall them from your Control Panel and restarted the computer?
When you open up the GPSInfo, is the Com Port field blank? If so, please right-click on its icon and select Properties. In the Compatibility tab, check the box that states 'Run this program as an administrator' under Privilege Level. Click Apply and OK. Then, close down all the programs that you have running since the device would not be able to use two software at the same time.
By the way, can you please register your product and generate a support ticket within our system? Please check your email for further instructions.