3 Demential Platform Mode
It really isn't that hard. You just need to switch gears. You need a tile set made out of BGOs that make diagonal paths, like Super Mario RPG. You also need to make a block with an arrow on it. Once you read the instructions, you can be able to make 3d maps like on Super Mario 3D Land and Super Mario 64!
1. Make a map with the BGOs you've made.
2. Create invisible blocks that you can place so Mario doesn't fall.
3. Add the block with the arrow that you made, that creates an event that switches from a forward and backward path to a left and right path. Here is an example.