since you are using multiple file extensions, In your database, you will need to store either the file extension by using the File extension binding, or the server file name.
You will need to use an update record server behavior for this, and make sure that the code for the update is placed after the Insert Record code.
In the update record server behavior, set the ID column to filter on the Properties_MainPropertiesID session variable to update the correct record.
Then on the results page, get the file name from the recordset.