I did go to :8181, but is said the expected folder wasn't found. I've never messed with other 3D printer boards or Drivers before and thought this was much more plug-n-play than it's turning out to be. I have Version 2.0.
could you take a screenshot of that error? or maybe your img file of RPI4b is old before April ? https://mega.nz/#F!qJgHzRwB!Sl6hKYqNDLAtKXnzekdB3A