Demo install dont want to work and after it became grey so its unclickable

Hi im using game addict on wordpress and i cant install the demo. (the demo notification it was working but he did nothing and I really need this to work before september and i just updated to the wordpress version and i cant make it work! I really need help :/ i heard of an update for this problem can i have a guess of when i should be able to download it? (sorry for errors im talking french)