It sounds like your scanner is not actually installed. I'd bet you have a corrupted device in your Device Manager that is holding you back.
Take another look at your Device Manager. Search through the list of connected devices when the printer is powered on and USB connected. If you can see any objects in the list that are related to the 3055 with a ? or ! then that is most likely your problem. You will have to right click the incomplete object and choose to update the driver software. When the hardware wizard pops up then direct it to the folder that contains the scanning drivers. Once Win8 knows where to find the driver files it should be able to complete the scanner install and grant your applications access to use the device. The scanner should register as an Imaging Device once it is properly installed as your Epson scanner does.
UPDs are print drivers, they do not have an impact on your scanner.