Sometimes you come at the end of the level with an incomplete amount of berries. this doesn't always means the end. jump/roll further up the hill (if there is one). you might discover a secret area.
when at the Loco-Roco screen, you might have mentioned a word looking like 'O3O3'. If one of the Loco's jump against it, they become red. if all letters are red, the Loco's will elevated all the way up. after all the Loco's are up, the platform will move, letting the Loco's slide down
If you're trying to unlock all the parts and find all the berries then it's worth knowing that every single level has many hidden rooms.
Some are easy to find and some are difficult. Be on the lookout for tell tail signs in the walls such as an alcove or dip in the wall. The walls themselves look ordinary, they only turn invisile when you pass through them. Most Berries and MuiMuis can be found in these hidden rooms.
HEY ITS 185139 AGAIN and when you see like a kind of dent in a wall or something try jumping through it or look at the top of your loco's head if the thing on top is wiggiling then your near a secret place
As soon as the level starts make sure to check everywhere to the left before moving to the right and getting through the level. There could be a secret room or barries ready for the takin'...
In some stages, there are enemies who disguise themselfs as a berry. They wiggle the berry and the leafes attavhed to it stretch out. If you manage to get caught by one, rapily press L and R to escape from it.
Small: Available from start[must beat first level]
Large: Collect 15 Mui Mui
Huge: Collect 45 Mui Mui
When in loco house mode place 2 bubble blowers like this >>><<< with 2 at the bottom to stop them walking out and watch as when they jump into it they warp into a thin line