Match existing cells by address in a worksheet

[singerla]

It may happen to have cells e.g. in Column B without an existing cell in Column A. pptx-automizer stumbles across this, because it cannot match existing and new cells by cell address. E.g. "B1" will be inserted as second cell, even if there is no value for A1, but an existing value for B1. B1 will exist twice, and excel complaining. Datasheets of charts will not open.