解析：
（1）C银行拒绝付款的理由不成立。根据规定，票据债务人原则上不得以自己与出票人或者与持票人的前手之间的抗辩事由，对抗持票人。（票据抗辩的切断）（2分）
The reason for Bank C's refusal to pay is invalid. According to the law, a person liable for a negotiable instrument may not set up against the holder such defenses that are available as between himself and the drawer or between himself and the holder's prior party or parties. （Bills defense off）
（2）A公司的理由不成立。根据规定，追索金额包括：①被拒绝付款的汇票金额；②汇票金额从到期日或者提示付款日起至清偿日止，按照中国人民银行规定的利率计算的利息；③取得有关拒绝证明和发出通知书的费用。所以，在本题中，出现追索金额超出汇票金额完全合理。（2分）
The reason of company A is invalid. According to the law, the sum and expenses for the recourse: ① the sum payable by the bill of exchange dishonored; ② interest, calculated at the rate prescribed by the People's Bank of China, on the sum payable by the bill of exchange, from the date of maturity or from the date of presentment for payment to the date of payment; and ③ the expenses for obtaining relevant evidence of dishonor and for dispatching notices. Therefore, it is reasonable in this question that the amount of recourse exceeds the amount of the draft.
（3）B公司的理由不成立。根据规定，持票人应当自收到被拒绝承兑或者被拒绝付款的有关证明之日起的3日内，将被拒绝事由书面通知其前手。如未按照规定期限通知的，持票人仍可以行使追索权。但因延期通知给其前手或者出票人造成损失的，由没有按照规定期限通知的汇票当事人承担该损失的赔偿责任，但所赔偿的金额以汇票金额为限。在本题中，虽然F公司没有在规定期限内发出追索通知，但是仍可以行使追索权。（2分）
The reason of company B is invalid.According to the law, the holder shall, within three days after receiving the relevant evidence of non - acceptance or non - payment, notify his prior parties in writing of the fact of dishonor. In case of failure to do what is stipulated in the preceding paragraph, the holder may still exercise the right of recourse. Where losses are caused to the prior parties or the drawee by delayed notice, the party to the bill of exchange failing to notify the relevant parties within the prescribed time limit shall be liable for compensation of the losses, but the damages shall be limited to the sum payable by the bill. In this question, although Company F did not issue a notice of recourse within the prescribed time limit, it can still exercise recourse.
（4）D公司的理由成立。根据规定，背书人在票据（背面）上记载“不得转让”字样，其后手再背书转让的，原背书人对后手的被背书人不承担保证责任。在本题中，D公司将该汇票背书转让给E公司，同时记载“不得转让”字样，然而E公司将该汇票背书转让给F公司，故原背书人D公司对E公司的被背书人F公司不承担票据责任。（2分）
The reason of company D is valid. According to the law, where an endorser writes "non - negotiable" on a bill of exchange and his subsequent party negotiates it by endorsement, the endorser shall not bear responsibility for guaranty to the endorsee of the said subsequent party. In this question, Company D transfers the bill of exchange endorsement to Company E, and writes "non - negotiable". However, Company E has transferred the bill of exchange endorsement to Company F, so the original endorser D is not reliable.
（5）E公司的理由成立。根据规定，票据债务人可以对不履行约定义务的与自己有直接债权债务关系的持票人，进行抗辩。E公司与F公司之间是有直接债权债务关系的当事人，F公司未履行约定义务，则E公司（票据债务人）可以拒绝付款。（2分）
The reason of company D is valid. A person liable for a negotiable instrument may set up defenses against the holder who has a direct creditor - debtor relationship with him and does not perform the obligations agreed upon. The direct creditor-debt relationship exists between company E and company F. If company F fails to fulfill its contractual obligations, company E （the person liable for a negotiable instrument） can refuse the payment.
