Does my chain slider look normal?

After an offroad ride, I took my chain wear slider off to inspect it.

I have kept the chain adjusted to Yamahas updated specs. This is a '14 with ~500 miles on it.

Another thing that worries me and if I'm at too low an RPM in any gear, I can hear the chain chattering... Is this normal? I hate having to hear it. Never had a slip, but the chattering is worrying.

The slider looks fine and the clattery noise at too-low RPM is normal.