Yes, we are using pygame.scrap, which is a easy-way to check the clipboard.
If the module is not here/compiled/not working, we don't have others implementation for it.
You could contribute here! Check kivy/kivy/core/clipboard/__init__.py for the interface that you need to implement, and check the clipboard_pygame.py for an implementation with pygame.scrap.
You could also check what's the error exactly (-c kivy:log_level:trace, and check back the issue, you'll have a traceback associated to it). If you don't have pygame.scrap, check why it's not compiled for your OS :)
Mathieu