Workflow - simple scripted validator

[Anneke Panman]

I have added the Jira Script-Runner plugin which has been working well in advanced searches. Now I would like to use it in a validator of a workflow transition. I have not been able to get it working so decided to try the most basic validator I can think of (without script runner). I have added the following in the Open->Create transition validator:

return false;

Even this does not prevent an issues from being created. I must be missing something basic. I am grateful for any advice or link to a site which explains this. I have read many sites but am still obviously not understanding it correctly.

Thanks

[JamieA]

Make sure you've published the workflow etc, if it's still a problem can you attach a screenshot of the configuration.