Occasionally I would have troubles getting Windows to recognize my Acoustic Edge. This would happen maybe once or twice a year, so definately not frequently. Usually just took the card out of the slot and put it back in, and Windows would detect it again. And just for the record, I've had similar issues with the Audigy 2 card I currently have.
The driver download from the site is complete, even though the setup says upgrade. When Windows does detect the new hardware and go through the new hardware installation procedure, just point it to the directory you extracted the files to, and the installation will take care of the audio control panel program that will then run at startup which gives you the options to set up the speaker configuration. It is the acoustice.exe file that is the control panel to set speaker configuration.