I downloaded the manual, and your player does support DLNA, although the manual doesn't specifically state it. On page 17 of the manual, it states this:
To play a file from a Home Network server via the player (Home Network player)
Select the [Video], [Music], or [Photo] category from [Media Server] on the home screen, then choose the file you want to play.
So, if you select the category listed above, Serviio should appear as a source. There's no profile within Serviio for your specific player, so Serviio has assigned the Generic profile. This might be sufficient for your media, but be aware that not all codecs are supported via DLNA. Page 36 of your manual shows the supported containers and codecs. Notice that Dolby TrueHD and DTS Master Audio are not listed as supported. It will play those codecs from an inserted BD disc, but not via DLNA. So if your media contains any lossless audio codecs, they will need to be transcoded. First experiment with your media, and when (if) you find something that doesn't play, or isn't listed in the titles, let us know.
There is nothing to configure or register. If Serviio is not visible on your network on any device, then there's a firewall issue with your computer most likely, or possibly an anti-virus program blocking access.
Dan
LG NANO85 4K TV, Samsung JU7100 4K TV, Sony BDP-S3500, Sharp 4K Roku TV, Insignia Roku TV, Roku Ultra, Premiere and Stick, Nvidia Shield, Yamaha RX-V583 AVR.
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