imovie wont create a new event

Hi

This problem is driving me round the bend. So far I have repaired disk utility, updated software to OS X El Capitan, deleted all large files just in case there wasn't enough storage. Uninstalled and reinstalled imovie twice and still I get this message. Can some please give me step to step instructions on how to solve this. I have read a few answers about creating a new folder for imovies in users, but not sure is meant by this. I have also researched other software as an alternative, but couldn't afford final cut pro.

Any help would be appreciated

Kind Regards

Andrew