The variable 'zzAtBOL' is not handled by the methods 'yypushStream' and 'yypopStream'. The appropriate code is missing in the file 'skeleton.nested'.
The method 'yypushStream' should save the variable 'zzAtBOL' too in the class 'ZzFlexStreamInfo' and then reset it to true.
The method 'yypopStream' should restore the variable 'zzAtBOL' too from the class 'ZzFlexStreamInfo'.
The class 'ZzFlexStreamInfo' should have the member 'zzAtBOL' too and save the respective parameter in it's constructor.
The variable 'zzAtBOL' should be handled like 'zzAtEOL' in the methods and the class (exception: inverse initialization at the beginning of a new file).
The appended file contains my proposal to fix the error (cumulative fix including ID 2942624).