Here's a work around that you should be able to use until we release a fix:

When creating a transaction check the box for "create unsigned transaction" and click continue. Export the transaction, then import it and sign it. If you use cold storage you are already doing these steps.

Then instead of broadcasting the transaction, click the link labeled "For more information about this transaction". That opens up a Transaction Info dialog. At the bottom, click the "Copy raw TX (hex)" button.

Paste the raw transaction to https://blockchain.info/pushtx  and click submit transaction.

Basically blockchain has already made the necessary fix to guarantee that the "Low S" is used, and applies it to raw transactions.