Thanks for the reminder, @robrigo! Below is a note that may be helpful for others trying to do this.

Problem: After following your instructions to send open Muse to a new Muse web wallet, my transaction kept failing.

Reason for problem: It turns out that there must be enough BTS remaining in your BTS wallet to cover the fee for this transaction.

Solution: After adding some additional BTS to my wallet and trying again ... SUCCESS!!!