Can you copy paste one of the ones you have found? I'd like to check it.
You can check that it works by doing this:
1) Please first backup your wallet.dat, or better remove it from your spreadcoin data folder and put it somewhere safe. So you can copy it back when you finished this test.
When you restart the wallet without a wallet.dat, it will create a fresh wallet.dat for you. That's what you want for this test.
2) CopyPaste the privkey (that starts with 7) of this address:
SPREADibexXvCPsfRR33FXzstqZ3J4Frih
7Qv2xq3Divx4kkxSeUonB5QuNd2VxTSyp4eTQirXk821xVUNCpW
DON'T USE THIS ADDRESS FOR ACTUAL PAYMENTS!Only use it for this test, to see that it will correctly show up in your wallet address list.
3) import it into your wallet by opening the Debug Console, and typing:
importprivkey 7Qv2xq3Divx4kkxSeUonB5QuNd2VxTSyp4eTQirXk821xVUNCpW SOMELABEL false
you can choose whatever you want for "SOMELABEL" , but keep the "false" at the end.
4) Now, Mr. Spread's wallet and even the newest bitcoin core wallet (and pretty much ALL other wallets I tested) all have this
BUG that they will show an imported address in the wrong list, the address book, instead of the receive coins list.

So what you need to do with those wallets is quit the wallet after the import and restart it. And then it will correctly show the imported address in the "Receive coins" tab.
The wallet I am working on doesn't have this bug, and won't require that you restart the wallet for importing vanitygen addresses.
5) After you have successfully tested this, stop the wallet again, remove the new wallet.dat, replace it with your old wallet.dat and everything is back to normal.