There is a bug in level 11. The layout of walls shown to the player is different than the layout the game believes the walls exist in.
I have the goal block connected to the 4 movement block in GB<->4B orientation. When I look to move the goal block down onto the goal I am blocked as if there is a wall there. I however can move into the wall space two blocks above the goal.
What the game looks like to give reference to what I'm looking at
| clear | W | W |
| clear | GB | 4B |
| W | Goal | clear |
What I believe it is based on how I can move
| clear | clear | W |
| clear | GB | 4B |
| W | W | clear |
I hope this was helpful