Using Plex HT or Open PlexHT on Hybrid Desk Station (HDMI) w/No Internet

I have my QNAP TS-253A all set up. I purchased it to use in my RV, and access my media library through the HDMI Out. It work fine at home when I have internet access, but when I put it in the RV, I can’t connect via Plex HT or Open Plex HT. I tried the fix from HowtoGeek.com (https://www.howtogeek.com/303282/how-to-use-plex-media-server-without-internet-access/) and with that I can access the media server using my phone through the wif, as the plex is plugged into a Ubiqutit airMaxx Router…

I also tried to enter the ip of the Qnap in the setting of the HT, but I think it is trying to authenticate my user and password via internet. Any way to bypass this ?

Also when I connect to the server on my laptop using the wifi, I can’t load the Media Server Application I get the error that I am not connected to the internet.

Appreciate any assistance. Basically want to use Plex on my TV connected to the NAS Server via HDMI, and use the Home Theatre App i have installed on my Hybrid Desk Station, but have no access to internet.

Thanks

I should add that the kodi app works, as well as the other players that come with the Hybrid Desk Station. I just would prefer to use the Plex app only.

Moved from qnap to OpenPHT forum.

Not sure why or how, but tried the setup in the RV, and Open Plex HT worked fine, even with no internet connection.