A Way to Assign CKSs to CTB-Based Scripts.

[SkyFrontier]

I've asked this in another thread, a user suggested me how to achieve it but I simply can't find how - after few hours wondering on this I concluded that it's impossible. My conclusion was based on a simple observation (after going upwards and downwards, Help and forums with no avail): Under Tools > Customize Keyboard Shortcuts > User, UDC commands are listed and each and every script can be CKS'ed from there. Toolbar Buttons seems to be listed only in Customize Toolbar, and even there there's no way to see specific entries.
This is important because CTB offers a more flexible way to categorize scripts, making it less crowded than User > Run Script. In the meantime we can't have submenus, this could offer a good workaround to have great scripts under CKSs while preserving visibility (netbooks and notebooks will benefit greatly on this, I believe).
Thanks.