How do you solve the furniture sliding-block puzzle in the PC game The 11th Hour?

competition/games/pc/11th.hour.furniture New

New entry, edited from material collected for the archive and not yet in a released version.

Problem

How do you solve the furniture sliding-block puzzle in the PC game The
11th Hour?

Clue 1: Move the pieces around until you can move the piano off the
board.

[ Editor: from a web page of solutions to the puzzles of The 11th Hour
(the sequel to The 7th Guest), maintained by doug@tbyte.com.  The
picture of the starting position (furniture.gif) was not collected. ]

Show solution

Solution:

Number couches 1-4
    1 being lower left
    2 being upper left
    3 being lower right
    4 being upper right
Letter Chairs A,B,C,D from bottom to top.
Letter Table T and the Piano P

    T, R
    B, R,U
    A, U,R
    3, L
    T, D
    B, R
    A, U
    3, U
    1, RX2
    P, D
    C, LX2
    A, LX2
    B, LX2
    4, D
    D, RX2
    2, RX2
    A&C U
    P, U
    1, LX2
    3, D
    B, D,R
    P, R
    C, DX2
    A, L,D
    2, LX2
    D, LX2
    4, U
    B, U,R
    P, R
    C, R,U
    1, U
    3, LX2
    P, D
    D, D,R
    4, L
    B, U
    D, R
    P, U
    3, RX2
    1, D
    A&C, D
    2, D
    4, LX2
    P, U
    A&C, RX2
    1, U
    3, LX2
    C, D,L
    T, L
    D&B, DX2
    P, R
    A&C, UX2
    T, L
    B, L,D
    P, D,R

-- Peter Wilke <http://www.fh-stralsund.de/~pwilke>

[ Editor: the page also thanks Marco Blom <M.A.Blom@research.kpn.com>
for an MPEG of the solution (/11thhour/ftp/furniture.mpg on the same
site). ]