Hi, I have found following video.
It contains great shortcuts (especially on "castle", "water" and "powerplant") and tricks how to have real speedrun :)Only for those, who want to finish speedrun as fast as it is possible
, without getting other achievements (they could be get using brilliant workthrough descibed by iTz Canada Eh)
Guy has passed whole game in less than 8 minutes
As I'm not so experienced gamer, I have made some mistakes, some parts were too difficult to use proposed way, but in general it helps a lot.
Using this video I have finished my speedrun in much less than hour.
Short description of my playthrough:
1-4 levels nearly identical as it is on video
5 level - 3/4 of level passed on the edges of walls. Was really hard to jump on the pipes, so I simply jumped down to this part of level and continue normal way
6 level - I have used catapult, but pushing it more closer to the mountain (as most as it was possible). After few attempts finally it worked
7 level - I went to the top of mountain as it is on the movie, but then didn't use thin plank to pass to the end of level, but simply run as it was in normal playthrough (destroy wooden dam, which runs big water wheel, etc.)
8-9 levels - similar as it is on videoedit: added additional videos with "Dark", "Steam" and "Ice" levels speedrun (contain some nice shortcuts, but quite hard to fully follow them)