If they are converters, I wonder how difficult it would be to make them standalone utilities that did the format conversion and nothing more (assuming there doesn’t need to be manual intervention). I’m sure there is complexity but it seems like StarOffice is a fixed format at this point, and OpenDocument has some previous fixed version that could be targeted.
Not that anyone should expect different, but Apple has not preserved backwards compatibility with their iWork formats and I have several legacy documents that I need to find old versions to open.