I was able to get it to work by opening the Form 4797 from the Forms view, rather than Step by Step. From there, you can enter the summary on the Smart Worksheet that pops up. In the final column labeled "PT", choose "II" (two). From there as you scroll through the form you can see it populates Part II Ordinary Gain/Loss from the summary you entered on the smart worksheet. For your summary, you can enter Short Term reported on a line, ST not report, etc. and same for Long Term. For e-filing, I'm not sure if we need to include the 1099-B as a "statement" though.
