If I understand you correctly, you'd want to give a contact a custom nickname but preserve their original name by appending it, example:
quote:
Real nickname: <([John])> 
Custom nickname: John
What you want to see: John - <([John])>
Unfortunately, this isn't currently possible. This was a feature back in Messenger Plus! Live 3, but then Messenger didn't have its own custom nickname feature yet like it has now. Patchou told us several times that he may re-add Plus!' own custom nickname feature when the nicknaming feature of Messenger itself isn't being extended. Until today, this hasn't happened yet, i.e. there's no way to preserve the original nickname using Messenger's own nicknaming feature, but there has been no response from Patchou whether he's going to re-add Plus!' nicknaming feature either...
As for scripts: no, not possible with the Plus! Live scripting environment. This is something which should be done by Messenger (or Plus! Live), not by a script.
About the remark of (!N): it may sound related, but it's not possible to use (!N) in a custom nickname and have it replaced by the real nickname. So that's a dead end there.
/ 
