I am on the same boat, I can preview pdfs using an ubuntu version of swftools but .doc or .xls won't preview. I have searched everywhere but I can't find any fixes or help on this issues.
I just get "the preview could not be loaded from the server". It didn't work on 3.2 so I upgraded to 3.3 and same issue, even tried manually installing latest version of open office on my debian server but that didn't fix the issue.
