Only thing necessary is for the Crypto market to mature.
CENT never disappeared, it just went offline after a rocky start.
Just be happy you managed to buy them dirt cheap while they were on the XPM/XRP/DOGE markets.
When the time is right, CENT will pop up again and continue with its main purpose.
Working on some stuff..
Will release more info in due time.
This is one of the first altcoins I invested, which is like 4 years ago.
If it still have a chance to pop up, that is really miracle.