Exist possibility of showing in gallery2 files of AutoCAD(dwg), Word(doc) and Excel(xls)?
Anything is possible, but no, nobody has done that work, you can file a feature request, but I seriously doubt it will ever be added. There are a lot of other solutions much better suited for collaboration, as I assume that's what you're wanting to do.
Unless you just want to host the files and not display them in the browser, then Gallery could do that.
Seriously, you want to take a look at SharePoint, it has native ability for Word and Excel and IIRC there are add-ons for displaying Acad DWGs or some solution from Autodesk. I've been out of the CAD world for a couple of years now and have ZERO interest in keeping up with it so I'm not sure what's available anymore. In the industry I'm in now, I know there are some solutions as there are county website that display AutoCAD DWG land maps that can be zoomed, panned, etc.
It would really help to know what exactly are you trying to accomplish. Just a site for showing files or are you doing some sort of collaboration. But really, to carry this discussion on, we should move this to General Chit-Chat.
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