|I did use Apache at one time on XP and Vista but didn't run into it altering Word docs. |
I set all the defaults to be MS rather than the Apache ones. It didn't always handle the newer docx (compressed files) properly though.
Can't vouch for it, but Libra Office is another which often gets mentioned and claims to work on Windows 8.
Keep watching for other ideas on here. If nobody chimes in it might be worth raising this as a new question.
Always pop back and let us know the outcome - thanks