Using dataselect on the Add Event html page

I have a custom page called venues.php where I am adding Locations to the DB, for use with the Events App.

On the Add Event in Perch I am trying to use:

<perch:content id="locationName" type="dataselect" label="Location Name" page="../venues.php" region="Venues" />

...but the dataselect box is not showing up at all. I have tried correcting the path to the venues.php page, and the region area is correct.

Not sure what I am doing wrong.