Thank you. my Augur tokens contract was frozen in summer 2017 due to serpent to solidity migration. Indeed there has been a further migration in summer 2018. I do not know how to unfreeze my funds on MEW and convert them into Augur tokens on the latest version. any advice?
You should have an equivalent token balance for the new REP contract at address
0x1985365e9f78359a9B6AD760e32412f4a445E862. In Mew you can access this by looking at your token balances.
If REP is not showing with your current balance you can add the address above as a "custom Token"