/scoreboard players set @e[type=FallingSand] wall 1 {TileID:35}

Edit: I think I found a solution. Now the problem that I have is that stacked falling sand entities are actually higher than they look.

/summon FallingSand ~ ~2 ~ {TileID:35,Data:5,Time:1,DropItem:0,TileEntityData:{CustomName:wall},Riding:{id:XPOrb,PickUpDelay:1000,Riding:{id:FallingSand,TileID:35,Data:5,Time:1,DropItem:0,Riding:{id:XPOrb,PickUpDelay:1000,Riding:{id:FallingSand,TileID:35,Data:5,Time:1,DropItem:0,Riding:{id:XPOrb,PickUpDelay:1000,Riding:{id:FallingSand,TileID:35,Data:5,Time:1,DropItem:0,Riding:{id:XPOrb,PickUpDelay:1000,Riding:{id:FallingSand,TileID:35,Data:5,Time:1,DropItem:0,Riding:{id:XPOrb,PickUpDelay:1000,Riding:{id:FallingSand,TileID:35,Data:5,Time:1,DropItem:0,Riding:{id:XPOrb,PickUpDelay:1000,Riding:{id:FallingSand,TileID:35,Data:5,Time:1,DropItem:0,Riding:{id:XPOrb,PickUpDelay:1000,Riding:{id:MinecartRideable,Motion:[0.0,0.0,0.0],CustomName:center}}}}}}}}}}}}}}}

/scoreboard players set @e[type=FallingSand] wall 1 {TileEntityData:{CustomName:wall}}

/execute @e[score_wall_min=1] ~ ~ ~ kill @e[type=Chicken,r=0]

So If I am for example using above commands (The long one stacks falling wool blocks and XPOrbs}, and let a chicken drop 5 blocks above the blocks where the stacked falling sand entities appear to end, it will still die before it touches them. The gap increases the more entities I stack.

Sorry I am posting this here, but somehow I cant get the command to work, no matter how I try it.

/scoreboard players set @e[type=FallingSand] wall 1 {TileID:35}

Was checking on Chunk Format Wiki, NBT Tag wiki, player.dat format wiki, google and so on and so on. Is there even a way to do this?

/scoreboard players set @e[type=Item] KillItem 1 {Item:{tag:{display:{Name:"Bob"}}}}

works.

(Also tried with UUID, but I have multiple FallingSand Entities)