Can I face a trademark issue with a Windows domain name (e.g., windows .io, windows .info, windows .net, etc.), even if I use it for non-software purposes?
It depends on the 'non-software purposes'. Microsoft has multiple Windows trademarks. They also have quite a few dead Windows trademarks. Other companies may have Windows trademarks as well. Have you researched it?
It your planning to use it with anything other than Glass Windows I would forget it. Your quite specific in mentioning just Software which alerts me to the fact that you might be considering a hardware related product/word Be aware anything that could be considered associated with this well know Trademark will find you in a mire of problems