Validation errors when using NativeXML Plugin for export issues

Hi,
We recently received a standalone journal based on OJS2.x. We want to move the journal to our production multi-journal installation based on OJS 3.3.0-5. I have managed to upgrade the journal from OJS 2.x to 3.3.0-5.

Am now trying to use the Native XML Plugin under “Export Issues” tab. When I select an issue and click on «Export Issues» button, it produces the following message:

Validation errors:

`Element '{http://pkp.sfu.ca}submission_file', attribute 'stage': [facet 'enumeration'] The value '' is not an element of the set {'public', 'submission', 'note', 'review_file', 'review_attachment', 'final', 'fair_copy', 'editor', 'copyedit', 'proof', 'production_ready', 'attachment', 'query', 'review_revision', 'dependent'}.`

…

Element '{http://pkp.sfu.ca}submission_file', attribute 'stage': '' is not a valid value of the local atomic type.

Element '{http://pkp.sfu.ca}issue': Missing child element(s). Expected is ( {http://pkp.sfu.ca}articles ).

Is it a problem of invalid XML and how can I validate the XML, etc?

Thanks in advance.

-Obi

I run into the same problem - is there any known solution to this issue?

-Armin