Should Article 145(2) of the Regulation implementing the Community Customs Code (CCIP), read in conjunction with Article 29(1) and (3) of the Community Customs Code (CCC), be interpreted as meaning that the rule laid down therein also applies in a case where it is established that, at the time of acceptance of the declaration for specific goods, there was a manufacture-related risk that a component of the goods might become defective during use, and in view of this the seller, pursuant to a contractual warranty towards the buyer, grants the latter a price reduction in the form of reimbursement of the costs incurred by the buyer in modifying the goods in order to exclude that risk?