Thank you for playing!
Yeah, you got there in the end with the combat. To attack was just click the card. There was meant to be animations for it but never happened! Also yes, I forgot to mention red is ATK points and green is DEF points. And you lost at a stalemate, this is just a condition that didn't happen a lot in testing and so the need for another resolution there didn't seem immediate.
But yes it was definitely helpful to see you play it! :)