Hi!
I just downloaded and tested LibreOffice 3.5 on Windows 64 Bit and my test result is depressing:
LibreOffice 3.5 corrupts my DOCX files completely, so that Microsoft Word 2010 cannot open it anymore!
I tried it with simple documents and it failed completely. Word doesn't even offer to recover the document, it is just unable to open it. I think this is a huge issue for most users of LibreOffice.
On Ubuntu 64 bit, with LibreOffice 3.4, the documents were only corrupted, so that Word had to recover it (with lots of lost formatting...) but it could open the file.
I experienced a similar behaviour with xlsx, too.
I don't know, why the importer for docx/xlsx is getting worse. I hope, you guys can use this information to improve LO.
Regards,
Philip