Yah I was super frustrated and read through all these posts and still couldn't figure out how to update the 1099-B form in web interface because it was super buggy and laggy. Then I saw @tbreisacher post saying they just entered totals. I went to my M1 forms and saw that totals are listed near the top then chose the option in TurboTax to enter manually and enter totals rather than individual sales. This was quick and seems to work fine.
