I'm having some trouble with this and I couldn't find any reported bugs. I'm using latest version from HEAD with vti amp installed. When I try to edit online office document it normally opens a new window with that URL on port 7070 and it offers to open or save document. I click open and document normally opens (read-write, no problems there) in excel 2007 but when I make some changes and try to save it it just stuck for a few seconds then brings up a "Document not saved" message. I've enabled full debug for sharepoint protocol but nothing shows up.
It's a Vista SP2 + Office 2007 + IE 8 client machine. Also, worth to mention is that passthru NTLM SSO is enabled and I'm pretty much confident this worked fine with basic Alfresco authentication although I didn't try it lately.
Any ideas?