Is there a way to use a variable within the title of a different macro?
For example, I might use an HTML form to prompt for %ClientName%, then later use a palette that includes macros with commands like "New Folder for %Variable%ClientName%" instead of "New Folder for Current Client".
I asked a very similar question a few months ago and "The Architect" gave me a way to solve my problem. However your goals were different from mine and the answer won't apply to you.
However there are people on this forum who probably know how to actually modify the name of a macro programmatically, so I think you need one of those people to answer you. However they might advise you of some other way to reach your goal.
If you're happy to have the KM Editor launch (even if hidden) you could use AppleScript to change the name of the macro -- I think I'd actually have a "palette Group" that you'd use to create the palette and containing macros I could rename, each of those with a single "Execute macro" action calling its respective "proper" macro.
You could even pass the name of the "palette" macro as a parameter to the "proper" macro so the client name would be available via %TriggerValue%