Glad you got it working - I haven't used Roadkill but it sounds OK, I used WinDD but you have to be careful because it will write over anything - including your system partition.
Lockups are probably heat related - can affect either the PI or the card, usually the card.
In Scotland heat is not usually an issue, trenchfoot is...
Also worth a check to see if the card has the latest firmware to make use of the 512K.