How to define a primitive device in Proteus?

I'm trying to make my own full adder and some other devices as a sub-circuit in "Proteus" and use them several times in a bigger circuit.

The problem is when you copy a sub-circuit you need to rename all of its inner parts, otherwise, the parts with a same name in two sub-circuits would be considered as one, therefore you'd get some errors.

So I'd like to know if there is a way to define a full adder of my own and use it like "74LS183" which is a primitive device, and by primitive I mean it has been defined in the library.

Solution

From answer posted here
It's in the Proteus Help file:

SCHEMATIC CAPTURE HELP (F1) -> MULTI-SHEET DESIGNS -> Hierarchical Designs

See the section "Module Components":

Any ordinary component can be made into a module by setting the Attach Hierarchy Module checkbox on the Edit Component dialogue form. The component's value is taken to be the name for the associated circuit, and the component's reference serves as the instance name.

after this you can use your new implementation of that component with your new name. for making it available at library see "External Modules" section of proteus help.