MRSS feeds parsers, are now different from text feeds parsers. Find some documentation here:
MRSS sub would look something like that:
Sub MrssParser(fileName$ as String, items as Object, metadata as Object)
Message$ = "Hello from MRSS parser"
slog=createobject("roSystemLog")
slog.sendline(Message$)
print Message$
' TODO inject feed information into items object.
End Sub