Most of the time it should be possible to use Standard Validations for defining Validations for an Dynamic Evidence Type Version. But, sometimes the validations may be a complex combination of many conditions or might involve calculations based on data from related Parent or Child Case Evidence instances. In such cases, CER Rule Sets can be used to define the Validations.
An administrator may specify the Rule Set to be used by enabling the "Use Rule Set" radio button under "Additional Validations" in the Validations Tab of the Evidence Properties, and then specifying the Rule Set using the "Rule Set Name" option.