Aperture 3.6 Export does not work

I'm running Aperture 3.6 on MacOS 10.10.3

When I right-click on a photo in Aperture and choose Export->Version nothing happens. Export dialog appears only on the second attempt.

The dialog itself is also broken - it shows Line 1, Line 2 and Line 3 only in export presets list.

Export Presets are defined in Aperture->Presets->Image Export... settings. I've tried resetting them. I've tried deleting presets.plist in Library. Nothing helped.

Any ideas how to work around this?

Thank you

Tanja