Crex24 will support the new software (version 5.0). Please remember to update your software as well.
My Qwerty coins on Crex24 exchange will be safe due to their claim on their support for the upgrade.
I got the coins from mining, and stored them directly on Crex24 exchange, that is likely reliable one.
I have not sold any of them, due to low price of Qwerty coin over recent months.