I lost you a little,
Yeah, sorry. I do that sometimes. Just thinking outside the box a little.
I still think the path is Nas wired to router, router wireless to laptop, laptop wireless to router, router wired to marantz so files are played wireless from Nas to laptop to Marantz.
I should have just left the answer to that question as: YES.
I was just wondering if I would get better sound quality if I went from a wired desktop running JRiver output HDMI to marantz. Rather than the convenience of wireless laptop running JRiver.
As long as your wireless network is fast enough to easily support the bandwidth required to play FLAC files, using your laptop the way you are should be fine. Have a look at the Bitrate of your FLAC files, and you should see it is much less than your wireless network can support. The sound quality should be identical using either method. If you hear stuttering, or delays in a track starting to play, your network may have some problems. Sometimes that happens in an environment where there are a lot of other wireless networks, such as in high rise buildings. But if you don't hear those anomalies, just keep doing what you are doing.
It would be a different story for high quality video, but for audio, what you are doing is fine.