O-oohkay not sure what is going on. I haven't touched any of the script files at all, so everything is original from the download you provided. I am running into 2 issues;
1) The score is not updating at all for me, it remains on 0 regardless of how many times I am getting it correct. It is adding the currency to my account, though.
2) Once I do guess correctly the question-mark card disappears, and if I guess correctly again after that then both cards disappear, though the buttons are still clickable.
GIF of glitches
HERE, and
HERE is a link to the game on my site itself.
Sorry for being a pain