Since MyEtherWallet is an ERC-20 based wallet, you will be able to load all of your coins at once with one public address.

Find your MEW public receive address:

Take your address and go to ZenLedger, and click on "Wallets/Import" tab.

-Select Wallet Import tab
-Select MyEtherWallet from the dropdown list on the RIGHT.
-Select the Ethereum/Altcoins/ERC-20 selection from the dropdown list on the LEFT.
-Enter your MEW public receive address (not shown below, but you will have copied it out of your MEW so you can paste it here)
-Click "Add Wallet" and all of your transactions will be pulled into ZenLedger.
-You will want to go to "Next Step" when you are finished adding wallets to refresh your transactions.

For a video that shows how to import wallets, please click below: