Conditional properties that support variables can be edited with the Define condition with variables property editor. A conditional property has a Boolean result (true or false). For example, the file filtering properties on connections are conditional properties.
The property editor discussed here offers a user interface to create comparison expressions with support for locating a variable and entering its arguments.
The example condition is true if the job being tested contains a single file smaller than 1MB or if one of the associated email addresses has the 'enfocus.com' domain.