After searching a bit, I didn't see some of the other problems mentioned.
Most importantly, the sales price and cost basis amounts are rounded down to the nearest $0.10 (e.g., $300.67 will be downloaded as $300.60), and number of shares is rounded to two decimal places, but is reported to three decimal places on paper 1099-B.
As I saw mentioned in another thread, the Description field shows the transaction type (e.g., phone exchange to ...) instead of number of shares and fund name or symbol. I found that TT fixes this automatically by going through Easy Guide for each sale; it changes it to number of shares and ticker symbol.
While doing this, I corrected the amounts. Also, some of the check boxes are incorrect, so I fixed these too.
I am using the Premier version of TT (I decided to splurge and spend the $10 instead of using the free version of Deluxe through Vanguard (Flagship), hoping that it would make some of the data entry easier, but so far, it doesn't seem to have done so). I have reported all of these problems to Vanguard.