It is a big limitation, but I got the idea from a Brian Eno song Commissioned by Microsoft,  it's basically just one melody but it's very good, I like the idea of making music in this style. But also, this is my first jam so i haven't figured out everything. Thank you for feedback!

Microsoft startup song:

I kinda like the idea of it being 20 seconds, it forces us to make the most out of a short snippet of music, and there is still a lot one can do in that time. Such as a victory theme or a short introduction. Though I will say the 5 days to do it is a bit much, even when considering some people might not be able to do it the day it starts. Overall, though, I get the idea.

20 seconds per a song. So you can make multiple 20 second songs. But 20 is the max, you can submit a 5 second song, or even a 1 second song!

You could try speeding it up a little bit, But if that alters the song in a way you don't like, I suppose can make an exception in the rules, just because you already put the work in.  

Great, I'm glad you enjoyed it!