I used the coinb.in UI to sign the transaction with the private key from
dumpprivkey 18UfvFPqRp5LXwhQTZnkUy5bZxyqrbujTm.
I manually constructed the nonsense output and lock time, so maybe that messed things up? Or coinb.in doesn't know how to sign it?
I didn't try using qt because I haven't been synchronized since the April bubble. I'm probably no further than block 230000
![Tongue](https://bitcointalk.org/Smileys/default/tongue.gif)
Coinb.in does know how to sign the TX. Did you try again?
If you can't use Bitcoin core, why don't you try lightwallets like Electrum and Multibit?
~~MZ~~