beginner problems

[Robert T Wyatt]

Hi all,

A couple of easy beginner questions for you:

I'm using 2.4.5 on MacOS 10.3.9. Why is there a second staff? Why does 
my bar check on my chords fail?

<<
\key f \major \time 4/4
\chords { d:m | }
\relative { d'8. a16~ a8 f16 d16~ d16 d16 f16 a16 d16 c16 b16 a16 | }
>>

Thanks very much,

Robert