Very easy on casual although frustrating. After the rock,paper,scissor section, you need to ollie up two ledges, then you enter a city part, head left and ollie at the top of the ramp to clear a gap, now you need to ollie three times in a row, i'd suggest doing the first one earlish so you have time to get the second one in. next you have an area with three pipes that you grind along. here you need to tilt the board just before you ollie to ollie across the gaps. Just to be clear, do not tilt the board until you intend to jump. You need to jump left, then right, then right again. practice that part until you have it. after that you have to ollie through the dragons mouth and then you don't have to do anything else for a minute or so and you'll reach the end.
I reccomend practicing the section with the pipes.
For the record i'd kept very calm when playing this awful game up to this point, but the pipe section had me throwing the board around the room.