I have worked with a PSOC 4 design that only supports addressing to 2 GB,
its here, and it works -
I just tried the emFile example program and am getting the same problem as you have described. I have a 8 GB microSD also. I am using an adafruit breakout board, which along with the SD card has been tested and works with an Arduino. The activity light blinks so there is some communication going on, but everything fails like you have described. Another score for freeware and simplicity.
Have you formatted the card using SD Formatter software?