Yeah, I know when friends cannot complete your game. From the time I was creating adventures in Spore I was making pure frustration.
And my brother never could complete my first game in Construct 2! Even after I told him about all the game mechanics. Check it out, if you can, I need an opinion.
And I found an awesome glitch. There is a snail that follows where Pepo goes, and if you stand on a platform that is above that snail and wait a bit the snail will start dancing. Try it