Thanks Alex, really enjoyed this game. I could see the Sokoban Bunny Tales influence (e.g. level 8 was like the bunny tales ice mazes, and the solve for level 13 required a similar strategy as a few bunny tales puzzles).
The secret bonus levels were a nice touch. I felt completely clueless as to how to reach them and was about to give up, when I read another commenter on here saying they were glad they persisted, so I made some educated guesses and ... eureka!
Thanks for taking the time to make this.