Hi Casten,
Sorry for the delay in responding, I could not get to my email this weekend. When you first plug the board in, you should see the blue LED flash twice quickly. If that happens the USB is working on the board. If the board thinks that it has established a USB connection, the blue LED will then turn on solid (but flash whenever there is data on the line). So I'm guessing you are not seeing it go on solid. If you get a chance to get on a Mac or Linux box, you could try to plug the board in since those operating systems will automatically detect any standard usb serial device -- so it should go solid blue there without any drivers installed. This will verify the board. Of course, I verify it before sending them out (and load the default sketch on) so it was certainly working just a few days ago!
I have a windows 7 laptop myself and am not having any issues. However, I do remember that it was a little tricky to install the "driver" since Windows 7 tries to hide the ability to manually install a driver from a file. And I do think that one other person had some driver install issues which I think resolved themselves by removing the driver, restarting windows, installing the driver, and THEN plugging in the Lightuino. But my machine was not so picky so it may not be that...
Since the Lightuino uses the standard windows USB serial driver, there really isn't any issue likely with the driver unless your Windows 7 installation is somehow messed up...
Cheers!
Andrew