To skip most of the second half of the level: just past the continue barrel (stars), use Diddy to bounce consecutively off a few purple "Kritters" (in the area of the second bonus room) and then off a green one while he is still standing on a small hill at the extreme right-hand end of the land area. After hitting the green "Kritter", bounce left and up as high as possible, to land on a nearby treetop. From there it is possible to jump into a high (usually off-screen) "barrel cannon", which blasts into a horizontal sequence that ends just short of the exit.
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