The Condition panel will only appear when you select the Use advanced condition option in the Test panel of the If action:

Type a valid OpusScript statement (or list of statements) in the box provided. This must result in a return value of TRUE or FALSE. In this illustration, a value of true is returned when the variable passmark contains a number equal to or greater than 70 and the coursework variable contains the word Completed – any other values will return a value of false.