Not bad, but could be a lot better...
Okay, first off, this is not a bad game. The graphics and controls are a lot better than the first one. The little storyline you added in there was clever and cute. And then of course Geno, which is just awesome on it's own.
However, level 7 is where the problems come around. There were several times where I jumped and fell through the platform, even though I had landed on it fairly evenly. That gets a little annoying after awhile, especially since you're sent all the way back to level 5. Then, when I finally managed to get through level 7, I couldn't get the star. However seeing as this was a demo I just assumed that was just the end of it, so I'm not going to grade you for that. Also, there were a lot of spelling mistakes in the texts, but this (of course) didn't affect the gameplay and isn't really too big of a deal.
Honestly, I don't want to critique you too much as I don't make games and I don't know how hard it is to create one. It does look like you put a lot of work into it and I think you deserve a score higher than what you have. I hope that you complete this game and submit it soon. I look forward to playing the completed version. :)