No, 512MB of memory. I have imgburn running fine on another ME based system.
Since you said the above I decided to fiddle around with the machine - multiple reboots, swapping around what programs are loaded on start up etc. Suddenly it started working - so I guess that's the route for anyone else who comes across this problem and finds this post. Just try adjusting what you have loaded on the machine and reboot to clear any "left overs".
Thanks for your suggestion anyway - it led to a fix eventually although I'm no wiser as to what was the culprit!