What follows are not the best or neatest solutions, but they are intended to get you to the point where you can complete the level.

*Update*
Apparently this was a bit too easy, and has been recently reworked and improved!



Dispenser and stamper


This is 100% of the puzzle right here. Blocks fall down, are automatically stamped, then the pushers get the blocks moving.
Rotators are kinda tricky to work with on 1x1 sized blocks, as it's fiddly to rotate them and then send them on their way.

We get around this by having the blocks "bump" them from behind. This works on max input rate just fine.

Good times. On to the next one.

A few tricky things here. The solution I'll show below only works at slightly slow input rates (which are adjusted by the square brackets. Also, note the dispenser and delivery pad play a bit of a trick on you, you need to rotate the odd numbered pieces to get the right finished product.

Rotating pieces is a bit weird, as pieces will only rotate if there's enough room for them to do so. I abuse that fact a bit to make the construction simpler.

Dispenser and rotatatron 5000

This is as simple as I could make it. The Block 1 triggers the first sensor, which sends Block 2 along the conveyor. The first block hits the two clockwise-rotation pads, before being nudged by Block 2 into the sensor, where the pusher slides it back into position. Now every second block is rotated. Lovely.

Welder


Similar to the last puzzle, the welder groups the blocks up into groups of four. You don't actually need 4 welders. Once four blocks are in position, the pusher sends the completed 3x4 block on its merry way.

Bonus: Don't miss the failure log (it looks like a suitcase) that's leaning up against the big orange cargo container.

So long!


Nothing to it. Get that landing light on it's way, and on to the next puzzle.

This is another one where the easy solution and the efficient solution look a little different.
The basic idea isn't too complicated, construct a cross of 5 blocks, and then stamp each of the 4 faces.

Convey the idea


This puzzle is a little more sensitive than most to the input rate, so this solution has it set to max (we don't want to disappoint our alien captors, after all).

Five blocks come down the top conveyer. The first 3 are welded and the remaining two are pushed onto the middle and lower conveyors.

Assembly area


Hopefully this makes our goal clear. We want the 5 blocks to fall into position. The last block to fall (which falls into the top-right space in the image above) triggers a sensor which activates three pushers to get the whole thing moving. Since the cross in in three separate pieces, we need to move it all at one unit until we can weld it together.

Welder and stamping section


Once the cross is welded together we only need the one conveyor. With that taken care of, the cross is moved past the stampers, rotated and stamped again. Nice!

Sometimes you just need to lift cargo, I guess.

I couldn't finder a way to make this work and look neat at max input rate, so we must content ourselves with a setting of +1.

Spawner and Sorter


By now the start may begin to look familiar. We need 6 brown blocks., and our array of a sensor with 6 pushers will do nicely. We need to weld each pair together, and funnel 2 2x1's to the left to make the body of our uplifter, and put the last one through the big blue grinder. Of course it gives us the resulting scoopy-thing back to front, but nothing a few rotatory can't fix.

Then it's just a matter of dropping them into place.

Yellow block spawner


Easy. Just weld them into a pair, and drop them into place as well.

Landing zone


The two body blocks and the yellow blocks land first, and the scoop lands a moment later. The scoop falling into place triggers the sensor, which activates 4 pushers, pushing the uplifter into the welders. Because of the way the blocks fall, a little bit of backlog for the 2x1 brown blocks isn't a worry; as soon as a scoop falls into place, everything clears up nicely.

In motion


A moment later the device will be welded, and the extra brown and yellow blocks will fall into place.

Extra credit: Delay the brown 2x1's just a little, and this set up allows it to run at max input rate (I managed 139 cycles). Science!

Saving the best for last, we need to make a giant claw.

This is a little more complicated than the rest of Resource Site 526.81, but like all puzzles in this game, you just need to break it down to manageable ideas.

Surprisingly, this solution runs just fine at max input rate.

Brown block spawner and sorter


This looks a little crazy, but the basic idea is sensible enough: We need to make 2 2x1 brown blocks, and send them left, and 2 3x1 brown blocks and send them right (to the grinder) as you can see in the image. By now the "sensor with a series of pushers and welders" idea should be easy enough to execute.

3x1 separator and rotater


This look a bit messy, but all we're trying to do is to separate the pair of 3x1 blocks, and rotate the right-hand one so it matches the goal.

3x1 separator and rotater in motion


There we are! The two 3x1 blocks are rotated and about to drop into position.

What about the 2x1 blocks?


The 2x1 blocks now need to be separated in a similar manner, and dropped into position below (via the conveyor halfway down the cliff). They're first rotated to make handling them easier.

White block and 2x1 welder



Yes sir, that's another sensor+pusher arrangement. The white blocks spawn quickly (and in a good location) so the extra platforms at the end of the conveyor act as a delay, so the brown blocks have time to get into position.

Once they are they trigger a sensor, and send this component off to meet up with the claws.

It all comes together!



The claws have already landed, so the component we just sent over here passes on through, welding itself to the claws as it goes. There are many ways of setting up the conveyors so the completed excavator gets to the delivery pad, this one looks odd but does the job just fine.

And there you have it!

Thanks to the clever people at Zachtronics for making such a great game!
Thank you for reading my guide! I hope it was some help.

That's probably it from me, I will leave it to the clever people to provide neat solutions to the other puzzles. However, I have cleared all the puzzles, so if you're stuck on something, let me know in the comments and I'll see about providing a solution.

Cheers!