Thanks, but that did not seem to work. It had already precomputed 100 addresses ahead. Nevertheless, I entered a 'Compute this many more addresses:' of 21, and clicked [compute]. After a brief interface, it showed 121 precomputed addresses. I then clicked [Done], which brought me back the Wallet Properties dialog. It still does not show those addresses known to the Watch-only wallet, but apparently unknown (?) to this Cold wallet.
If you are using a version older than 0.96.0, you won't see the addresses in the wallet properties dialog if you haven't actually "used" the address (i.e. clicked the Receive Bitcoins button). However the wallet still knows about those addresses and should be able to sign for them.
Thanks again. My Cold system is on 0.93.3. My Watch-only is 0.93.2.
So on the Cold install, Clicking the [Receive Bitcoins] button brings up the Select Wallets dialog. If I select the relevant wallet, and clock [OK], I am faced with an ominous warning:
(X) Careful
(!) Armory is not online yet, and will eventually need to be online to access any funds sent to your wallet. Please do not receive Bitcoins to your Armory wallets until you have successfully gotten online at least one time.
...
[Cancel] [OK]
This being an airgapped system, it will never be online.
However the wallet still knows about those addresses and should be able to sign for them.
I believe you that the wallet still knows about the addresses. But how does one use them to sign? If I Tools>Message Signing/Verification...; Sign with Address; Address Book; Select Wallet...
OH! There it is!When I click [Select Wallet], it exposes the next 'missing' address from the deterministic sequence.
Thanks for your patience - I think you have walked me through it.