You first have to get the blue switch palace to enable the main path but the fact that so much can lead you into getting stuck before that or being forced to take hits is really obnoxious and confusing. For example, a powerup is provided in the area with the P-switch, but you're supposed to enter the smaller pipe, and you still can when you're big, but you have to duck-jump out of the path in the next room. A Spiny will walk into you likely before you finish - best to just not get the powerup in this case. If you dismount the line-guided platform at all in the first cave room, it can't be reset by moving the screen since there's not enough space to trigger a reset, and you have to go down the hole and die because the pipe's not re-enterable. I could never figure out the necessity of the P-switch and springboard in this level. After that, it becomes a lot more clear.