Thanks so much for playing El Cid! The key is there, but you'll just have to keep clicking on the props. My playtesters found it fairly quickly, however, they did not notice some of the other bugs you pointed out. So I am really grateful for your help! I will work on those and make a patch after the GameJam voting is finished.
When it comes to the music, I was a bit limited in time, so did not have time to get something made specifically for the game, but rather used free music I found online that fit the theme, but I agree that battle music should definitely be extended.
I'm really happy that you enjoyed the game concept! And yes, I will continue to work on it and make more installments in this IP.