Hi Vasilis,
the game crossword has problems with words containing the German letter ß.
I created a crossword game basing on a glossary with some German words (in brackets for you the English word):
Haus (house), Straße (street), Auto (car), Vögel (birds), weiß (white)
The problem is, I cannot enter a ß, because the input id="wordentry" converts it immediatly to SS because of the CSS rule text-transform:uppercase for this input element. That's why the game shows the error that the right word has one letter less:
I have found that some other languages are affected too. See here: https://developer.mozilla.org/en/docs/Web/CSS/text-transform
Thanks, Stefan