Start a new game, beginning from the first level, and choose the "Expert" difficulty level (because that one unlocks all rats and objects). Do not use passwords, but feel free to save the game (and load it later, if needed). Then follow this guide (which is translated from a Steam guide linked below)

Level 1 with 1 rat: Cannon Rat (rotation=38, timer=9)
Level 2 with 1 rat: Cannon Rat (rotation=0, timer=1)
Level 3 with 2 objects: Lung Rat, Wooden Board (rotation=28)
Level 4 with 1 rat: Batter Rat (rotation=34)
Level 5 with 2 rats: Batter Rat, Bomber Rat
Level 6 with 2 rats: Batter Rat, Bomber Rat
Level 7:
Level 8 with 2 rats: Batter Rat, Bomber Rat
Level 9 with 2 rats: Batter Rat, Vacuum Rat
Level 10:
Level 11:
Level 12 with 4 objects: Batter Rat, Bomber Rat, Wooden Board, Wooden Box
Level 13 with 3 rats: Batter Rat, Bomber Rat, Lung Rat
Level 14 with 3 rats: Archer Rat, Batter Rat (rotation=34), Bomber Rat
Level 15:
Level 16 with 4 rats: Archer Rat, 2x Bomber Rats, Lung Rat
Level 17 with 4 objects: Balloon, Cannon Rat (rotation=25, timer=45), Vacuum Rat, Wooden Board
Level 18 with 4 objects: Balloon, Barrel (rotation=30~40), Bomber Rat, Lung Rat
Level 19 with 2 rats: Archer Rat, Cannon Rat (rotation=47, timer=6)
Level 20 with 2 rats: Lung Rat, Vacuum Rat (rotation=89)
Level 21:
Level 22 with 2 rats: Batter Rat, Tractor Rat
Level 23:
Level 24 with 5 objects: Archer Rat, Balloon, Batter Rat, 2x Bomb Rats

As you probably know, the physics engine for this game is awful, and it may take a lot of tries until the ball decides to follow the path you wanted. So, don't give up and keep trying! And, yes, there are 18 levels listed in this guide, but you only need to complete 15 of them using fewer objects than planned.