Fill Question

[Xarzu]

I am doing a step-by-step tutorial called "Ray of Light". I am a newbee, so no laughing. I am at the poing where I am trying to replicate this cool design:

http://images2.flashkit.com/tutorials/Special_Effects/Ray_of_L-Mark_Fen-1/ray_fill.gif

I managed the gradient:

http://i67.photobucket.com/albums/h292/Athono/helpa.jpg

Then I used the free-form tool and another button to nudge the shape into place:

http://i67.photobucket.com/albums/h292/Athono/helpb.jpg

Now, do I fill in the space bettween the right white edge of the warped triangle and the left edge of the letter?

The Tutorial says "Once created you need to fill the lights. Use the gradient tool, and the lock tool to create the perfect effect. "

I do not kow what the lock tool is? I am using CS4 and I think the tutorial was written for a different version.