The challenge of the day is to beat the eighth level of Murky Depths without using the piece on second screen. Alternative mode only.
(http://greywool.com/misc/shots/nsPieces1.png)
(http://greywool.com/misc/shots/nsPieces2.png)
Quite easy, you don't even need to flip the first piece.
Edit: Yay, posting in 4-year-old threads. Also, added spoiler.
(http://i.imgur.com/EQk6wfP.png)