Thanks for that although I still don't think I understood. So a player's registration with a club and their contract with a club are two separate entities?
Clubs used this to hold on to a players registration even though his contract had expired, stopping him form going to another club. Now this has ended because if a player is within 6 months of his contract and negotiates terms with another club, his current club have to hand over his registration for free.
So with Colo, even if Newcastle cancelled his contract, because he isn't within six months, they can hold onto his registration and won't be obliged to pay him, because his contract isn't valid.
Unless he takes it to court and tests the validity of a his registration lasting beyond his contract
My own slice of the internet is here: http://www.maulsquad.com - it isn't very good.