Problem with Starting Balance in Projected Balances

What might work is recreating the account.  You would have to deactivate it from downloading transactions, create a new account setting it up for downloading, remove any transactions that are already downloaded in the original account and to move the transactions to the new account.

Unfortunately, because of a bug in Quicken that they have refused to fix in all these years, moving transactions between accounts is a lot harder than it should be.  The problem is that if you use "move transactions" it will prompt you on every single reconciled transaction.  There are two methods to work around this problem. One is to use Copy Transactions instead of Move but note it will not copy attachments.  The other is to first set all the reconciled transactions to cleared, and then after the move set them back to reconciled.

In all cases the way you can do an operation on multiple transactions at a time is to select the first transaction, and then go to the last one and hold down the shift key and right click on that transaction.  That will both select all the transactions in between the two and bring up the menu where you can change the reconcile status or do the copy/move.