Question regarding custom constraints

Hi

I am trying to create custom constraint to capture designer intent on schematic. I am able to define constraints and list them in constraint manager. Now I would like to restrict  some parameters to be set on constraint only and not on the members.

I read following in the cadence document but I am not clear on how to achieve this.

A parameter declaration on the constraint dictionary (propdict.def) allows the parameter to be created on either the constraint or the member. To restrict the use of parameters, for example setting values on members or the parameter range and combination, you should use the verifyCB callback (see Validation and Verification Callbacks). Illegal parameter settings and member combination should yield warning messages and the callback should return nil. For example, your verify callback could allow a parameter to be set on net members only, or only on constraints. Moreover, it could restrict that only the first member can be, for example, an instance. Any logical check, with respect to constraint members and parameters, can be performed using the verifyCB callback in order to restrict parameter and member usage.

Ideally I would like to display a parameter only for constraint and not for it's member (just like Priority parameter for  Net Priority). Also how to prompt user to enter value for a parameter (should it be through verifyCB callback ?)

Here is example of my propdict.def and config.xml file for custom constraint.

propdict.def file

occPropGroupType MyCustCons1 {
        verifyCB=MyCustCons1VerifyCB;
        legalPropName MyCustomCons1Param1 {
                valueType = enum;
                valueDefault= "None";
                valueRange = "None foo bar";
        }
        legalPropName MyCustomCons1Param2 {
                valueType = enum;
                valueRange = "TRUE FALSE";
        }
}

config.xml file

 <ConstraintType>
   <Name>MyCustomCons1</Name>
   <GUIName menu="MyMenu">FancyName</GUIName>
   <MinMembers>2</MinMembers>
   <MaxMembers>2</MaxMembers>
   <AllowedMemberTypes>net</AllowedMemberTypes>
   <Param><Name>MyCustomCons1Param1</Name>
        <GUIName visibleInEditor="true" summary="ValOnlyIfNotDefault">Param1</GUIName>
   </Param>
   <Param><Name>MyCustomCons1Param2</Name>
        <GUIName visibleInEditor="true" summary="ValOnlyIfNotDefault">Param2</GUIName>
   </Param>
/ConstraintType>

How can I configure so that designer will see Param1 for both constraint and it's member but Param2 is only visible for constraint and not for it's member ?

How can I prompt user to always enter Param2 value when the constraint is created ?

Thanx,
Rushang