Ahh that works as long as you check the box to show unused addresses! Thanks!
I'd really like a way to indicate to the offline client how many addresses to show in the main interface. Since the addresses are all generated and available, this doesn't seem to be a difficult proposition.
The offline computer automatically keeps a lookahead of 100 addresses (you just don't see it). Everytime you sign for a transaction, it's going to re-extend the key-pool to keep 100 addresses lookahead. So if you have used 2 addresses, the offline computer has the first 102 addresses computed. If you sign a tx for addr 51, it will computer the next 49 addresses so it is "tracking" the first 151 addresses. As long as there are no gaps more than 100 addresses (I might have upped it recently to 1,000), then you will have no problems. And if you do experience any issues, you can just use the expert interface to generate the extra addresses.