Excellent work Chris.
The warding on the BiLocks is weak -- as you have discovered
![Smile :)](./images/smilies/icon_e_smile.gif)
-- because it doesn't extend right through the plug. Xeo broke his also with heavy pressure.
As Bezza wrote, it looks like a QCC. I bought three oval BiLocks from Bezza and that's how they are: there is nothing on the back which can be used to free the core. Two small ball-bearings hold the core in place. Ordinarily the two notches on both sides of the control key allow the ball-bearings to move inwards thereby unlocking the core. If you pick these the ball-bearings will also fall inwards (because there is no key) and you should have been able to push the core out from behind with some firm pressure.
Rear of BiLock QCC:
![Image](http://farm7.static.flickr.com/6143/5942750948_f7370ddf0c_b.jpg)
Nothing to unscrew, unclip, push or pull.
QCC partially removed to show retaining ball-bearings:
![Image](http://farm7.static.flickr.com/6128/5942195195_f68b478ce5_b.jpg)
User key that has been converted into control key with the help of a chainsaw file:
![Image](http://farm7.static.flickr.com/6147/5942751806_28e4c1d879_b.jpg)
The notches give the ball-bearings room to fall into which frees the core.