Downloaded APK fails when android checks the package

This is a super-simple proyect:
https://x.thunkable.com/copy/5080c46ef60501727403844fd82e4a26
Just a couple of components cause just need to fix this problem.

I already downloaded the apk file in Chrome and Edge.
I tried to install the apk file in Android 7 (tablet) and Android 9 (phone). Also tried in Andy Droid.

My err msg is in spanish: “Se ha producido un error al inicializar el paquete.”

Of course I configured the “accept unknown apps or sources” on each Android device.

Do not know what else could I do. Any ideas? Thanks in advance.
PLEASE: Can anyone of you import this proyect into Thunkable X and créate the APK and try to install it on any device??? Tell me if Works!!!, please.