Making the square block does not require using all three switches, but all will be used eventually. The square block indeed needs to be made on the ground using the pistons/pushers, and if I understand your method correctly, you are already using the right two. There is a way to hit both switches while you are still on the upper platform, let me know if you'd like more details.
Ok, so from the ground level it’s much easier to slide a row of blocks in order to put multiple blocks in motion on different paths. From the upper level it’s seems you would have to actually push the blocks that would trigger the buttons. So if I’m thinking about this the correct way , that is where I’m stuck. How can you push blocks in any particular direction and manage to get them moving on different paths and or different directions?
When you say that the diagonals will still be made on the upper level do you mean they will also be made by standing on the platform or that they will be made by using blocks that are stacked(as I did for the earlier solution)?
Regarding the making of the square block, the only thing I’ve come up with is that one of the blocks needed to push a button has to be in place (presumably stacked on a square block)immediately to the left of the diagonal so that when either the player or a block is pushed onto the diagonal block, the stacked block to the left is sent left and either the player or the block pushed is sent downward. This seems doable aside from it seeming not possible to have that stacked block in place and be on the platform. If you use the risers on the right to elevate yourself then you lose a useful block with that method
If there’s anything further you are willing to say or correct my thinking in regards to making the square block, feel free:
The first block, the block that will hit the upper left button cannot be pushed directly to the button. It has to travel left, one space above the button, and then loop back (requires a down block) in order to synchronize with the object that will hit the lower button. In order to affect the split motion of the 2 blocks, the first block needs to be on another blockdirectly left of the diagonal block. It isn’t possible to get that first block in place without pushing one of the down blocks off of the platform in order to transfer it. Atleast one more down blocks are necessary for block #2 to reach the bottom button. Down ward blocks are necessary to create down right blocks. Two down right blocks are needed to reach the exit and need to be transferred to it ( the exit) by way of being stacked on other blocks. It’s not possible to elevate any blocks in the level after the risers have been used once.
Obviously these can’t all be true and my common sense tells me there must be a way to keep two downward blocks up on the platform while making the square block I’m just spelling out the thought process. Tough puzzle. I believe the only two other I know that started it both already gave up.
The timing for this part is tricky, hopefully this explanation helps (also, just to confirm, you won't need to drop more than two downward blocks to the ground and you won't ever need to raise blocks off of the ground again after you get onto the platform with the blocks). The paths to each button from the diagonal don't need the same number of pieces, as you can essentially speed up a path by having another stationary block sitting along it. As an example, suppose a block is sitting two spaces away from a diagonal and you push a new block onto that diagonal. After the first time step, the block is one space away from the diagonal. On the second time step, it pushes the stationary block onto the tile three spaces away from the diagonal, so you get an object three spaces along the path in only two time steps. You can use this trick to synchronize the button presses even if the paths aren't equal length.