Hello!
I'm at section "4.2 WHITEBOARD COORDINATE SYSTEM" .Im trying to run this command :
load ServoPositions
SimplePlotterApp(s,mL,mR,LeftMarker,RightMarker
and it keeps showing this 
screanshot attached)
What should i do?
Hi, are you still having the issue? If you are having please make sure you have all the necesssary support packages and the correct project files. And then if you are still having issues please write to us at support@arduino.cc and we can have a better look at the issue.