Creaky Floorboards

1c set adv to 2c passing LSh | 1c+3c turn BH ; all ½ LSh Reels3 on sides (3,1,2)
All S&Link3 but 3M & 2W turn LH to centre facing corners they just left ; 1c lead path of snake pass to end in 1st cnr pos as M side: 1W,3M,2M & W side: 3W,2W,1M
Repeat 9-16 from new psns to M side: 2W,1W,2M & W side: 3W,1M,3M
Modified bourrel: 2W+1M & 1W+3M set advancing | full turn BH while{4} 3W & 2M chase ½ way cclw ; all set to P up/dn centre | turn BH to sides (2,1,3)
Longer instructions are at