I have little experience with Pier. I don't understand why, when I select the "Environment" selection, I receive and error: "MAOptionDescription is abstract" This comes from: MAOptionDescription >>error: "Create a new instance of the receiving class and checks if it is concrete." self isAbstract ifTrue: [ self error: self name , ' is abstract.' ]. ^ super new I don't understand the error when looking thru the debugger thread. Any help? Where can I look? brad