The following procedure has helped solve many issues with Keynote:
1 Close all iWork applications.
2 Uninstall iWork using an application removal tool.
Appcleaner works well for this purpose and is freeware.
To be effective, all iWork applications have to be removed, not just Keynote.
You must use an application removal tool to completely remove the iWork installation.
3 Empty the Trash.
4 Shut down the Mac, then restart and press the shift key immediately after the startup sound, release shift when the Apple icon appears. Allow the Mac to boot up to the desktop, it will take longer then usual as the hard drive is being repaired.
5 restart the Mac
6 Reinstall iWork using either the original install files or log into the Mac app store and down load and install
7 Repair permissions: Applications > Utilities > Disk Utility > First Aid:
click on your system disc in the drive column and select Repair Disk Permissions
8 open Keynote and test
Post back to let us know if this was successful.