No it's very simple you had goods on tick and dont want to pay for them, can't get much simpler than that!
errr why are they playing dirty, you owe them! If anything you have welshed on the debt, that's pretty dirty. You don't seem to dispute that yet it is somehow them getting out of order! You really need to look at the facts, you owe the money and yet you seem to think it's your right to try and get out of paying. Do not be surprised if no one will lend to you again. Forget the paper work, you owe the money end of. Look up the word "Honour" in the dictionary.