In case you have issues with transfer transactions not being generated correctly:
For best results manually enter transfer transactions into your register BEFORE you download transactions from the bank which contain the transfer confirmations. For recurring transfers use scheduled reminders and enter them a day or two before the due date. Be sure to use distinct Payee Names for each transfer / credit card payment to avoid confusing Quicken - memorized payee entries. That takes the guesswork out of the downloading process. Because a correctly entered transfer transaction already exists in your account registers, the process should just match the downloaded transfer transaction to the existing one in both accounts.
Manually review all downloaded transactions, one by one. Select the downloaded transaction, review the register transaction it will be matched to or the new transaction that is about to be created. Make changes as needed to Payee Name, Category, Memo, etc. and then click Accept for the single transaction. "Shampoo, rinse, repeat" for all remaining downloaded transactions.