There's a "hack" to duplicate layout.
Save your project as a folder (or open your capx in a zip program like winzip or 7zip and extract the files to some folder).
In the folder "Layouts" go and make a copy of the layout you wish to duplicate (ex "Layout 1.xml")
Rename the copy (ex: "Layout 2.xml")
In the file itself, change the name in between the <name></name> tags.
(ex "<name>Layout 2</name>")
Go back to the root folder and open your .caproj in the notepad.
Look for the line:
Right after you should have:
Copy this line and paste it right after (with the same indentation). Rename to the name you gave to the layout copy earlier (ex: "Layout 2.xml")
Save the .caproj, open it in C2, you should have a clone of the previous layout standing in your Layouts folder. This layout is currently aimed to use the same event sheet as the original layout.
It's a bit hacky, so be sure to make backups of your projects before using it and use at your own risks ^^.