On the phone with support for almost 3 hours today on this issue.  Updated the program six ways to Sunday, but still generating blank 8453.  Per technician, not a big deal to send IRS a blank 8453.  

Same issue as others have mentioned - MW codes.  Also, the checkbox at the bottom of the Form 1099-B worksheet does not check yes even with Code M unless Code W is included.  Code W toggles that checkbox.  What a mess!