Import external project ondemand cloud

Dears.

I have an instance of Jira running in our servers, but we are studying to migrate the Jira to the atlassian ondemand cloud.
We started a test instance (one month trial) and I have imported all of our projects to the cloud.
We decide to use only one of this imported projects in the trial phase and in the second phase to use all projects in the cloud.
To do it, I need to test if is possible to export the project, which will be used in the first phase, and to import it again definitively in the second phase (after all projects were imported again from current production).
But when I am testing this approach I got the error 404 in the URL
https://<example>.atlassian.net/secure/admin/views/ExternalImport1.jspa
This error happens when I click on the item "Import External Project" in the menu " Projects".

Please, could someone help me?

Thanks,

Augusto

PS: I follow the suggetion at
https://answers.atlassian.com/questions/252021/import-external-project-ondemand-cloud

Jason%20Worley%20%5BAtlassian%5D
Jason Worley [Atlassian] · 2,742 karma · 2 hours ago

From the description, it sounds like the JIRA importers plugin is disabled on your OnDemand instance. Please open a support ticket at support.atlassian.comand we will ensure it is enabled for you.