It sounds like you are in Notation view, not chords view. The L button allows you to enter note-based lyrics. This will insert lyrics based on positions of notes in your melody track. If you are in lyric entry mode, pressing the enter key will advance you to the next position (i.e. the next note). You can also use Tab to advance, or Shift+Tab to go back to the previous note.

You don't have any notes in your melody track so it is saying it can't advance to the next note when you press enter. One thing you can do, if you don't have a melody, is put in some "temporary" melody notes where you want the lyrics to go. You can toggle into editable notation mode and enter them in using your mouse... don't worry about what notes they are, just that the placement in time is about right. Another way to enter notes is to Record MIDI and tap the notes with your mouse on the onscreen piano, or tap your keyboard keys on your qwerty keyboard (to do this, enable Wizard Play-along mode under the Play menu).

Once you have entered/recorded your notes, you can then enter note-based lyrics. Afterwards, you could delete your temporary notes by right-clicking on the melody track --> track actions --> erase.

Andrew
PG Music Inc.