Doesn't export to .odt

I’ve tried to export my files as .odt documents and although I have installed OO I get the message that I need MS Word to export files as .odt

This is a serious problem. I don’t have MSWord installed, export to .odt isn’t allowed and export to .rtf appears buggy. I am content to live with occasional crashes but until there is a reliable way of exporting editable text from Scrivener, I can’t afford to use it other than casually.