Amending tax return: How can I add additional stock transactions when the application does not allow me to add more (tech error to blank page - local version)?

I begin to amend my return, I follow this path: 
- Wages & Income
- Investment Income
- update investment sales
- '+ add more sales'
- Stocks, Bonds, Mutual Funds
Then I encounter a blank page. Is there a workaround for this? I prepaid to avoid incurring a penalty, but need to file the amended return.