on for the Upgrade table states that the property specified in this field must be a public property and must be added to the 
SecureCustomProperties property. WiX automatically appends the property specified in this field to the SecureCustomProperties property when creating an MSI. 
Each UpgradeVersion must have a unique Property value. After the FindRelatedProducts action is run, the value of this property is a list of product codes,
separated by semicolons (;), detected on the system.</p>



        </td>