Pretty easy, but it's a tutorial level, so it makes sense.
Move to the right out of the spotlight. The switch near the short wall turns on another spotlight to reveal the passageway to the exit, but none of the switches stay down unless something's on them. (You, the lantern, or a block) Get used to that. Jump over the short wall and stand on the other switch, which turns on the spotlight above, and drops a real block to the floor. Hop back over the short wall, push the block against it (holding down the switch) and hop through the hole revealed by the spotlight to reach the exit.

Notice that the moving spotlight reveals two holes (one above your current area, one on it) and that the spikes aren't real. One problem: even if things aren't real, they can still kill you if you touch them while in shadow yourself. So to avoid dying on the spikes, follow the spotlight through them.
You can't climb up the ladder all the way, because it isn't truly real. So dismount at the higher platform where the block is, and push it so it lands on the button far below when the spotlight reveals the holes. (If it misses the button, that's ok, but you'll have to go down there and push it on properly, then follow the moving spotlight through the shadow-spikes again) Once the only switch in this level is pressed, the left-facing spotlight removing the top of the shadow ladder turns off, allowing you to climb the ladder all the way up to the exit.

A lantern! Cool, a portable light source! Also a portable weight. Follow the instructions and press "X" to pick up the lamp. This thing will be your best friend in the levels to come, but unfortunately cannot be carried from level to level. Anyway, follow the instructions again and hold "C" to turn it on. Release "C" to turn it off. Couldn't be simpler. Hold "C" and find the hole in the box you're in. (It's right above the "hold 'C'" instructions) Fall through and keep the thing on to pass by the shadow-spikes. When you get to the switch, turn the lantern off and press "X" again to put it down on the button and turn off the spotlight, thus revealing a shadow-ladder leading to the exit.

Ooh, deadly darts! Not good. Don't think of bringing the lantern down there, the darts are real and WILL kill you. Anyway, go right and pick up the lantern, then go left with it on to reveal a hole in the walkway. Drop through, but quickly turn the lantern off once you're past the first hole so you don't drop through the second one below it and get killed by the darts. Go over to the block (with the lantern still off, mind you!) and push it above the switch on the right. Go ahead and turn on the lantern now. (Make sure you're left of the block so you don't get a dart to the belly.) You and the block will fall to the lowest platform. If you positioned the block correctly, it should simultaneously guard you from the darts, and keep the button pressed, which unblocks the passage behind you; the one leading to the ladder. It's ok to turn the lantern off now. Go over and stand on the other switch, (which unblocks the exit) and leave the lantern there. Exit.

This level has your first shadow-block (it's the farthest one) and three walls blocking the exit. The three switches get rid of these walls, so you'll need to keep all three down. To do so, first pick up the lantern if you haven't already, and go over to the closest block. Turn the lantern on, and you and the block should fall to the lower level. Push the block onto one of the buttons and leave it there. Now, you can either leave the lantern on the other button, or take it with you. I like to do the latter, since it makes for a faster descent then climbing down. Either way, climb up the ladder, and push the shadow-block to the switch on the upper platform. If you have the lantern, be sure not to turn it on here, or the block will disappear and you'll fall unless you're on the leftmost part of the platform. Once the shadow-block is on the switch, go back down to the lower platform (The lantern can be used to fall down there, if you prefer) and leave the lantern on the remaining switch, if you didn't already. Leave.

Ok, this one can be tricky if you don't know what's going on. The block right in front of you is actually a shadow-block, so it'll disappear if the spotlight touches it, leaving you pushing nothing. In any case, push the block a bit, then retreat from the light so you don't fall into the spikes. Once the light returns right, go back and continue to push the shadow-block. when the light comes again, this time jump in place as it passes, and then leave the shadow block on the switch, which allows you to grab the lantern. Turn it on to pass the shadow-spikes, but watch out! Four of them are actually real, and will need to be jumped over. Try to jump as the spotlight opens up more room above your head. It isn't necessary, but it helps if you're afraid you won't clear those spikes. Make sure your lantern is on the entire time, of course. Leave the lantern on the button to unblock the door, and exit.

Pick up the lantern, but DON'T TURN IT ON YET! If you do, you'll fall into the spikes. Not good. The closest switch turns on the spotlight on the right side of the level, the switch past it moves that light up and down its wall as long as it's pressed. Hold the second button down, and move the light as far down as it will go. (If you have it right, when the light is on, it should remove the entire lower section of the shadow-spiked wall) Keep the lantern, and use it to drop the block from the higher platform to the lower. Push the block onto the light switch and leave it there. Then climb the ladder again and leave the lantern on the third switch, which unblocks the door. Exit.

The three blocks on the uppermost platform are not all the same. The rightmost one is actually a shadow-block, so ignore the two switches at ground level for now and go up there and push it as far to the right as you can, leaving a space big enough so you can push it left later. Push the middle block near it, then go back down to the ground-floor switches. Like the previous level, one moves the left-facing spotlight up and down on its wall, the other turns it on. Unlike the last level, neither of these buttons need to be kept down. Anyway, move the light up to the highest platform and turn it on so the real block you put next to the shadow-block falls down one level. While you're at it, move the light down to the second level and drop the block to the third. Then go up there and push it onto the switch. Go back up to the highest platform and push the remaining real block near the shadow block, and drop it down like before. Push the real block onto the next switch, then push the shadow-block (you did leave enough space, right?) onto the topmost button, finally unblocking the door. Leave.

The two buttons on the ground floor remove walls that are blocking the door high above you. You can't see it from here, though. The button on the step moves the lit spotlight up and down along its wall. Yeah, that's a theme here. Anyway, go ahead and stand on the button for a while. As you do, you'll notice that one small part of the ladder is real. Leave the spotlight directed at that section, and climb all the way up to grab the lantern. Notice the button near it that removes the third blocking wall. You'll have to put the lantern here when you're done with it. In any case, go down and push one of the blocks (it doesn't matter which one you do first, but be mindful of the gap. It's kinda tricky) onto the spikes, then drop onto it and turn the lantern on to remove the spikes (and the platform underneath them) and drop the block to the ground floor. You'll fall in front of the block, so go over to one side and push it onto one of the switches. Then go up and do the same with the other block. (Careful you don't step on the light mover button) Once both blocks are on the switches, go up to where you found the lantern, and put it on the button you noticed earlier. Leave.

You're on the home stretch! 5 more levels after this one!
here, you have another moving spotlight removing a line of shadow-spikes, just like in level 2. However, this light moves quite faster than the level 2 light. You may have to jump forward a few times to keep up. Once you make it, climb the ladder, then jump over the block and pick up the lantern. Push the block onto the switch, which removes a blocking wall near the door. The platform nearest the ladder is just shadow, but the spikes underneath it are all too real. Instead of dropping through, go past the shadow-spikes under the quickly-moving lamp again; which is exactly like before, except now you can go at your own pace thanks to your trusty lantern. Back near the beginning of the level, just past the spotlight's range, is another hole blocked with a shadowy platform. Drop down and keep that lantern on to subvert the shadow-spikes and drop into the small passageway with the switch. Put the lantern on it to remove the last blocking wall, and go on to the next level.

Ah yes, this one. You have to push the blocks onto points where the downward-facing and upward facing spotlights combined give them the most-uninterrupted path to the outer switches. (The inner switches move the spotlights) The left block is fine just being positioned right over its outer switch, but the right block will have to trek a bit further; place it a square or two left of the inward-protruding upper-right corner. Then line up the spotlights to roughly where the blocks are to drop them straight through. Push the rightmost block onto its outer switch, and go on.

One of my favorites cause it's nice and short, but it requires quite a lot of guesswork. Allow me to do it for you. Pick up the lantern, and stand just under the center of the right side indent in the ceiling before turning it on and falling through the platform and the shadow-spikes below. If you lined yourself up correctly, you'll land on a three-square real platform if you don't turn off the lantern just before landing. Turn it off now, though, and stand just to the right of the switch you can see below before turning it on again and falling down there. Put the lantern on the switch and leave.

Another favorite, cause the idea is ingenious. Once again, one of the buttons moves the spotlight along the ceiling, and the other turns it on. Position the light above the block on the left, then turn it on to drop the block. Drop the block on the right, too. Then, put both blocks on the buttons. Stand on one, (it's ok if the block's centered on the button) and use it as a stepping stone to jump to the center platform once it's awash in light and the shadow-spikes vanish. Then jump to one of the "staircases." The switch on the left moves the light if you didn't put both blocks on the switches, but if you did, it stops the light. Kinda useless, in that case. Anyway, the light will dispel the wall blocking the door as just shadow, so pass the shadow-wall when it's gone to leave.

One more after this! Those darts shooting out are just shadows, so pick up the lantern and head for the ladder with it on. (The switches next to the spotlight turn off the shadow-darts and unblock the door, respectively. However, putting the lantern on them won't do you any good) Put the lantern on the switch up the ladder, which turns off the spotlight and reveals a shadow-block where you started. Climb the entire length of the ladder, then go across the overhanging platform, and push the shadow-block onto the button that turns off the dart shooter. With the danger gone, go retrieve the lantern, climb the ladder, and drop off the overhang again. Now, here you have two choices. Either: 1) put the lantern on the button that unblocks the door and go through (which is most likely what the creators intended) or 2) Push the shadow-block onto that button and use the lantern to pass by the shadow-darts and leave with it. This is the only level where you can actually leave with the lantern, but as I said before, it doesn't carry over anyway.

This is it, the final level... and it sure looks that way. The shadow-box near you is currently protecting you from the shadow-darts, (as evidenced by the fact that they don't show up in the spotlight) so good for it. Push it into the spotlight, but don't go too far. The shadow-block continues to protect you from the shadow-darts, even though you can't see it now. Go up the ladder, and push the real block through the spotlight (And technically, the shadow-block itself) and park it just above the two buttons you can see below the platform, just past the lantern (need I tell you to pick it up?) Turn on the lantern, and the block should fall in a hole. If you don't, go drop in. Make sure your lantern is still on until you go in there to avoid being spiked by a dart. Push the block onto the right button to remove a blocking wall, and stand on the button left of that to move the spotlight. Move it 'till it's illuminating the hole, then leave the area left and climb the ladder there to go push the shadow-block into the spotlight again. Move the spotlight to the left of the shadow block, then go around again and push it onto the button closest to the shadow-dart shooter. This will remove another blocking wall.
To remove the last wall, first, re-position the spotlight illuminating the hole. Then, go left and put the lantern on the remaining button. (not the light mover) Climb up to the middle pathway for the last time, drop into the hole, and leave to finish the game. You did it!