The newly implemented functionality to claim RAD rewards in Tinlake is pretty slick and easy to handle. Go to https://tinlake.centrifuge.io/ and connect to your wallet (e.g. MetaMask or Ledger).
Click rather on the button “Claim rewards” in the center of the page or “Claim RAD” in your account’s information. The claim rewards-page contains very useful information about your personal investment portfolio (invested DAI, portfolio value, your daily and earned rewards in total) and system-wide rewards for all investors.
Before the RAD can be claimed, link the Polkadot extension to your Tinlake account. Make sure the addresses from the extension and Tinlake are the same (if necessary, change the format in the extension’s settings “display address format for” and choose “Centrifuge Chain”) and start to link. Important: once the extension is linked to Tinlake it cannot be undone!
The syncing takes some time, after it is finished the rewards can be claimed and your RAD are transferred to your wallet. The display for “claimable rewards” and “claimed RAD” changes as well.
If you run into any troubles you can contact the support on Telegram https://t.me/CentrifugeSupport