Hey there!
I spent ~15 minutes with the demo. Here are some notes:
I agree with a lot of the comments from TripleSmeven. I will say I liked the installer for the game. . . I need to look into how you did that, because it made it feel professional and polished to come as a real "program" instead of a zip file of the build.
- Good job on the opening cutscene! It wasn't exactly representative of the game, but the cinematography was good. I didn't need to skip it, but having the option is always good.
- I don't understand Spanish, so I couldn't read the intro text. It did fade a little quickly. Perhaps pad it with a few seconds. I try to go for ~2 seconds for a decent pause, or ~4-5 sec if I really want to emphasize something.
- There is a hefty lag between the Control screen and the main menu (when going back to the main menu).
- For the opening level, there are a lot of mechanics all at the beginning. The platforms are a little too stacked, and I died a lot just trying to get to the first moving platform (the one above the first one would clip my jump).
- If you haven't / don't already, try taking a look at GMTK (Game Maker's Toolkit) on YouTube. This video is great for getting a decent starting ground on simple platformers:
- I also died like 4 times trying to get the purple vial until I finally realized there were spikes. I think TripleSmeven's suggestion of blurring the background could help, or more outline / brighter colors on the hazards if you want to keep that pretty background.
- For the second scene, it might help to have the falling platforms be slightly different than the non-falling platforms. But it was a good surprise!
Good luck!