Adding parameters to checks can be done programmatically using EKL.
This page discusses:
Real
let param(Real) param = ThisCheck.GetAttributeReal("ParameterName")
Integer
let param(Integer) param = ThisCheck.GetAttributeInteger("ParameterName")
String
let param(String) param = ThisCheck.GetAttributeString("ParameterName")
let param(Real) param = ThisCheck.GetAttributeReal ("ParameterName")
let ListValue(List) ListValue = ThisCheck.GetValueList("ParameterName")
let ListValues(List) ListValues = ThisCheck.GetListOfSelected ("ParameterName")