Drop Zone On Payment Request Fluid Page

Has anyone been able to get a drop zone on the the payment request page (PR_SUMMARY_FL) to work?

I've been trying with a custom subpage that contains fields from a custom table.  Nothing is getting saved in the custom table.

Found this information E-FLUID: Drop Zone is not Inserting Data Into Custom Record (Doc ID 2541487.1)

"In this case, the REQUEST_ID field is a Key field in the custom table, but it is not a Key field on the delivered PR_COMMON_WRK table.  The requirement for a page/subpage relationship is that the Key fields have to be common between the two for this to work."