I FINALLY GOT LEVEL 26
IF I remember it...
Arrange the 3 at the bottom to give access to central area. Push one thru so you can go around the top to push upermost to middle. Then travel around right side to push the corner one so it is above the right opening to the central area.
Then, push the one in the lower doorway back down. The one under that goes all the way to the left to get around it. Push the single box on the far left through into the central area. Then go back around to push it back out of the way and move one all the way to the right. Then go to the top and take care of the one that was in the corner. Then you can go back and arrange the rest so that the 2 uppermost ones get pushed across the top and down through the top opening.
Push one all the way to the left, push one of the original 3 from the start corner into place. Leave the last one down there out until you take care of the two at the very top. Then push the one in the middle back out to position the others, push it all the way to the left, turn around, go around the gray block and push it into the hole.
I think I needed 88 moves. I worked on this for almost a month. Now I am stuck on 27.