Re: I had been using old bitcoin-qt and now I seem stuck

Blockchain.info import wallet feature via wallet.dat no longer works, at least to my wallet and experience.

If you want, you can just open Bitcoin Core, go to Help>Debug Window>Console and use

Code:

dumpprivkey "Address"

to extract the private key. Import the private key to another SPV wallet. Make sure that the correct wallet.dat is in the data directory.