Problems with the SoftwareSerial Library

The 'ÿ' represents -1, the value returned when you try to read from (Software)Serial and there is nothing available to read. Are you checking SoftwareSerial.available() before reading?

the 'SoftwareSerial.h' text does not turn orange

The keywords.txt file for SoftwareSerial still refers to NewSoftSerial, so I wouldn't worry about that.