Restore working directory after computing org-version
Sebastian Rose writes
> 1. Open an *.org file you can export to PDF. Ensure the file is not
> located where your Org-mode sources are (org-*.el files). Choose a
> file, that includes some images or a SETUPFILE using relative
> paths.
> 2. M-x default-directory RET
> to see the value of that variable in the current buffer.
> 3. C-c C-e p
> to export to PDF and verify it works.
> 4. C-c C-x !
> to `org-reload'
> 5. Now repeat steps 2 and 3. Note, that the export fails.
Sebastian also submitted the basic patch to fix this