Here is the full list of all 12 Falling Plus achievements.
In one game, cleared Rounds 1-10 having smashed all blocks in matching pairs.
Cleared Round 1.
Achieved a Combo, by smashing Wally and a matching pair of blocks at the same time.
Entered Arcade Mode and inserted a coin.
Smashed a matching pair of green blocks (Survival/Burning Igloo excluded).
Put out a fire (Burning Igloo Challenge excluded).
Cleared Round 5 by smashing all blocks in matching pairs.
Smashed 1000 blocks in total.
Earned an extra life by achieving the required score.
In one game, scored 50,000 points or more.
Earned the top spot on the local score ranking table (any settings).
Earned a score of at least 10,000 points on either the Survival or Burning Igloo Challenges.