Coin age resets whenever coins remove, sadly
I just did some more investigating. It looks like there is indeed some incompatibility between the old SSD private keys and the new wallet (unless I just didn't wait long enough). I was unable to import my old private key into my new wallet, but when I created a new address and sent coins to it like you suggested, I was able to import that key instantly.
So, are we going to try to get everyone to move their coins to an address generated by the new wallet (before 9/10 gets here) or are you going to change the source?
For anyone reading, his solution was correct. Obviously, backup your wallet before making any changes to it.
Create a new address. Send the balance (maybe break it into smaller payments if it's a huge balance) of your wallet to that address. Go to help->debug. Go to console. dumpprivkey youraddress. Copy that into a txt file. Backup that wallet and move it out of your appdata/roaming/sonicscrewdriver folder. Start wallet with no wallet.dat. Go to help->debug->console. importprivkey yourprivkey.
That should work.
edit: Another thing. We should maybe somewhat coordinate this as we have to wait 3 days before we're able to stake again. If you have a large balance, maybe send some of your balance today and the rest of 9/8 or something like that.
There is no incompatibility between the privatekeys, If anything there is a difference between the wallet formats. If you had waited for it to index all your transactions and then closed and reopened your wallet you would see that it had moved from the address book to the receive addresses.
When I first started testing I had my old wallet that I was still using. I changed cause it took forever for it to go through each transaction and see how it was related to mine.