I have tried using Send Coins > RBF Control. It sets source to the right transaction. I have set a new receive address in my wallet, and set Amount to Max. However, I am getting Size: N/A, Fee: N/A, and Preview Transaction says it has an Invalid spend value. Using other amounts makes no difference.
I'm really not sure what I am supposed to do here. Is there any documentation on this I can read? Armory doesn't seem to have a help file.