Except the button support appears to be a bit dodgy.  I have the 5 way working very well as a joystick, but it won't read the memo pad button as a fire button unless I press it repeatedly about 10-15 times in a 3 second span, then it takes it.   I also had to set the screen to buffered 256 to display properly. 
Other than that, looks and works very well.  A bit of slowdown, but as was said, it's only the first, and frankly, it's one of the best "first releases" of any emu I've ever seen.  Amazing job!