I am not sure that you will be able to use that file from Escient with Wizz.it. It was designed for PEPV2 and supplies a code database with the 232 strings.

You may be in a position where you have to install PEPv2 on your machine, get the 232 codes from the database and paste them back into the Wizz.it editor.

Contact Escient to see if they have a file compatible with that version of Wizz.it.
You may want to contact Marantz to see if an editor is available.

However, beware that that remote has been discontinued and I cannot locate software on the Marantz site. Could be that I've let my Owner's Circle account expire.