www.com-property.com/downloads/admin.controller.txt
download this file replace .txt to .php
replace your file in
\administrator\components\com_properties\admin.controller.php
in your properties panel click in "Create CSV"
system create file called
\administrator\components\com_properties\properties.csv
you can edit this file
first field is ID of property
if you use ID then property will be updated
if is empty ID system will be create new property.
when finish in your properties panel click in "Import CSV"
test please in test server