To add platforms, just remix and then go to the sprite named "ground" and go to the 3rd costume. copy that one and put it in the "level" (the first costume). then you can just shape that block how you want! The edges of the block you placed might be a bit fuzzy. To fix this, turn the 1st costume of "ground" into a bitmap, and then back into a vector. this will unfortunately mess up curves, though.
Type the letters "f r o g" for frog mode!