Integrating events app with categories app

Hi there,

I have a category set called locations which I use for various collections.

I'm trying to use this for events, rather than replicate the categories in event app categories.

The template works fine: I just pop in:

<perch:categories id="locations" label="Where is this taking" set="locations" required="true" />

But I'm struggling to filter by this field. Is this possible / a bad idea?