My feedback: I love the concept of this game - it reminds me of both Lemmings and Chilly Willy combined into one. It adopts the Game Jam's theme nicely, emphasizing blocks as its main game component, and more than just merely loosely added as a non-central theme of the game.
I especially like how the game's challenge gently progresses over the first few levels, giving the player opportunity to learn how to play the game and slowly develop skills.
In my opinion, as good as the game is, it could be significantly improved with just the following 2 revisions. 1. Pressing the directional arrow should change the wizard's facing direction first without immediately also moving the wizard to the adjacent floor tile. This way, the wizard could create ice blocks in certain locations without the need to move several times to reposition into the needed floor tile. 2. Some unobtrusive background music playing during the gameplay would add much to the user's enjoyment and overall appeal of the game.
It is good to see a game made using AOz Studio. Years ago, I dabbled in STOS (the ancestor of AMOS), which is an ancestor of AOz Studio. More recently I've been using the excellent AGK (AppGameKit) tier 1 (a dialect of BASIC), but I also strongly considered using AOz Studio which appears to be another fine product which uses its own BASIC dialect. Nice game submission, and thank you for helping to inspire me to continue with my own BASIC game projects!