[Jeff Hinkle]

Just clicking on the layer won’t create a selection. I’m guessing earlier in the tutorial, he explained about CTL/Command-clicking (that’s CTL on a PC, Command on a Mac) the thumbnail of the layer in the Layers palette. That will load the opaque pixels of that layer as a selection. Then you should be able to use Modify>Contract.

The next step is saying, while you still have the selection available, select the Rectangular Marquee tool (that’s the one that looks like a box with a dashed outline) and use it to deselect the bottom part of the current selection. Hold down ALT/Option. Your icon will gain a little minus sign. Now if you click and drag, any area of the current selection you go over will be subtracted.

Then it’s just a matter of dragging with your Gradient tool with a white-to-transparent gradient. It will fill the shape made by the selection, white at the top, fading to nothing at the bottom.

Hopefully that helps clarify the points, and I didn’t make you feel like a dummy.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

Put your black and white layer (we’ll call it A) above the layer you want to mask (B). Set the Track Matte (shows up as TrkMat in the timeline panel; you may need to hit the “Toggle Switches/Modes” button if you don’t see it) on layer B to Luma Matte. Anyplace that’s black in A will be transparent in B, anyplace white will be visible. Anything gray will give partial transparency.

Now, if A is a black layer with transparency, you’ll want to use an Alpha Matte. Same principle, but anyplace that’s opaque will be visible in B and anything transparent will likewise be transparent. If you’re going Alpha Matte, the opaque area color is irrelevant. It could be black, white, rainbow colored, a lovely photo of a sunset, doesn’t matter. All After Effects looks at is opacity.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

With Pen tool selected, hold down Alt/Option. Your cursor will change to a little crooked “V” shape. Click and drag.

With the Move tool selected, hold down Ctl-Alt/Command-Option.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

I believe the shortcuts are mostly if not completely identical. The few times I’ve had to go cross-platform, I don’t recall any shortcuts not working right. The basic conversion to remember:

CTL = Command
ALT = Option

One caveat: The modifier keys are in slightly different positions, so that may slow you down a little. Many’s the time I hit the Windows key while my hands were running on shortcut autopilot.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

Your video size looks to be 720×480 SD, and your comp is definitely an HD comp. Not sure what your comp size is, but since your magnification is only 33%, I’m guessing it’s probably a 1080. Change your comp settings to match your video, or drag your video to the New Comp button in the Project window to make a comp at the exact size and pixel aspect ratio of your footage.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

Sounds like you want the Graph Editor. Look for the little squiggle-line icon on the top right of your layer list in the Timeline. Select the parameter(s) you want to adjust, click the graph editor to access your motion graph, click again to get back to your keyframes.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

You can still reconnect your footage even if it is precomped. Just go to your Project window and find the original sequence in the list. Right-click the file and select Replace Footage… and navigate to the original files. However, if by “precomp” you mean you actually rendered it out with the missing frames and imported the resulting movie file, then no, you can’t reconnect that. But you should still have your original sequence comp in your project that you can pull back in the original sequence files.

As to how could the links break without moving them? You’d be surprised. I’ve had entire multi-layer images go missing from AE overnight with the computer off. Computers like to mess with you sometimes. It’s their only joy.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

In your After Effects Preferences, check out the Audio Hardware and Audio Output Mapping section. If you have your computer set to send all audio to the headphones, changing these two to System Default should send all your audio to your ‘phones.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

By “colored blocks” do you mean color bars, like you see on TV accompanied by a test tone? That means After Effects has lost the link to your elements.

When you import something into AE, you don’t actually bring the items into the program; you just create a link to the files stored on your hard drive, external drive, what have you. If you move (or remove) those files, AE can no longer find them and puts up a color-bar placeholder to let you know it can no longer show them. No need to rebuild the animation, though. Just relink the missing file (right-click on the missing file name in your Project window and choose Replace Footage… and select the appropriate file) and your footage should reappear with all your previous animation work intact.

—
It is easier to destroy than to create.
More fun, too.

[Jeff Hinkle]

There’s several ways to do this. I don’t have CS6 yet, but I imagine they haven’t changed this functionality much.

With both images open, drag the layer you want to copy from the Layers palette to the new document. If you’re using tabbed windows, select the layer in the Layers palette and then drag the layer from the image (NOT the palette) to the tab of the second document and wait for it to open. Then move your pointer into the new document and release the mouse. In either instance, if you hold Shift while dragging, the layer will center itself into the new document (if its pixel dimensions are different from the original) or place itself in the exact same position (if its pixel dimensions are identical to the original).

You can right-click the layer in the Layers palette, choose Duplicate Layer… and in the resulting dialog box, choose your new document from the Destination pop-up menu.

You can even do copy>paste, but I don’t recommend it. That’s a lot of data to have hogging up RAM you could be using for other things.

Good luck and welcome to Photoshop.

—
It is easier to destroy than to create.
More fun, too.