The letter S in solutions means "spacebar" which switches control between the two halves (cubes) of the block when it is split. D of course means down.
Level 20 (S=spacebar) D,L,D,R,D,L,U2,R,U2,L4,D2,R,U,L2,D3,L,D,U,R,U2,R,U2,R3,D3,L,U,S,L,U,D,R,S,L5, D5,R5,D
To beat Level 8: R2,D3,R2,S,U3,R2 (R - right, L - left, U - up, D - down, S - spacebar). To enter stage 8 the passcode is 499707.
Level 23 D,L,U,R,D2,R,U,R6,U,L,D,R,L3,U5,R4,U,D,L6,D4,L7,U3,R2,U,D,L,U,R,D2,R,D3,R8,U,L, D,R,L4,U3,S,D,R2,D3,R4,U2 (S=spacebar)
Level 26 (S=spacebar) U2,L3,D,L3,D,R,U,R2,U2,R2,D,R2,D,R2,U2,L2,U,L6,D,L3,D3,S,U3,L6,D,L3,D3,U2,R,U, L,D,R,U,R2,U2,R2,D,R2,D,R2,U2,L2,U,L4,D5,R3,S,U3,L4,D5,R2,L
Level 15 (S=Spacebar) R4,U2,S,U5,R3,U2,R4,D2,U2,R2,S,L2,R,L3,U,R,D,L2,U,R,D,L3,D,L3,D4,L,U,R,D,R7
Level 20 (S=spacebar) D,L,D,R,D,L,U2,R,U2,L4,D2,R,U,L2,D3,L,D,U,R,U2,R,U2,R3,D3,L,U,S,L,U,D,R,S,L5, D5,R5,D
To beat Level 8: R2,D3,R2,S,U3,R2 (R - right, L - left, U - up, D - down, S - spacebar). To enter stage 8 the passcode is 499707.
Press the spacebar. This is indicated by (space) or by "S" in the solutions.
Level 23 D,L,U,R,D2,R,U,R6,U,L,D,R,L3,U5,R4,U,D,L6,D4,L7,U3,R2,U,D,L,U,R,D2,R,D3,R8,U,L, D,R,L4,U3,S,D,R2,D3,R4,U2 (S=spacebar)
Level 26 (S=spacebar) U2,L3,D,L3,D,R,U,R2,U2,R2,D,R2,D,R2,U2,L2,U,L6,D,L3,D3,S,U3,L6,D,L3,D3,U2,R,U, L,D,R,U,R2,U2,R2,D,R2,D,R2,U2,L2,U,L4,D5,R3,S,U3,L4,D5,R2,L
Level 15 (S=Spacebar) R4,U2,S,U5,R3,U2,R4,D2,U2,R2,S,L2,R,L3,U,R,D,L2,U,R,D,L3,D,L3,D4,L,U,R,D,R7
Use the spacebar (S) to move controls between the cubes. The blocks move independently, but rejoin automatically if they meet.
S in a solution means "spacebar" which is how you switch control of the two halves (cubes). This is in the instructions. (see related question)
Level 28 (S=spacebar) L,D3,R,D,L,U,R,D2,R2,D2,R3,U3,L,U,L,U,L,U,L,D,R2,D,R,D,R,D,R2,D,L,D,L2,U3,L,U, L,U,L2,U,L2,D,L,U,R3,D,R,D,R,D,R,D,R,L4,D3,L5,U2,L3,D,S,L7,U2,L3,U
There is no level called level d. Levels show up as #s only.
The S in the solution codes is the spacebar, not the S key.
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