I have been learning a lot about Mura the last couple of weeks while building my first Mura plugin, but I have also had a lot of frustration because some things work differently when you are developing for a front-end page vs. a back-end (admin) page.
In the Mura Developer Documentation it states:
The Event scope simply wraps the current request's event object which contains merged data from both the CFML FORM and URL scopes.
If then goes on to say that the following code should return values from those scopes.
<cfset $.event('property') />
So if I have a URL variable like ?test=123, then this code should return the value '123':
<cfset $.event('test') />
This seems to work fine on pages I create for Mura display objects for the front end of the website, but for pages in the admin area of the site, this method only produces [empty string].