Hi Beno,
Thanks for the response, been on the forum’s a while however could not remember by login in detail. 
Recent changes to Exchange driven mail saw the expiration of my old email address, hence I could not use your remember password facility. Let me know if there is a away I can merge profiles ?
Long story short, short story long, back to the topic at hand.
I am also fairly confident that the problem at hand is router driven.
It is the first time I am using this router and it requires a very good understanding of how to setup the firewall and traffic rules. Something I have limited knowledge of.
The router is the Teltonika RUT950. Very powerful in functionality.
The finishing goal is to use the cellular WAN as a back door for maintenance and system upgrades via VPN. Strangely enough I have managed to get all this working on eth1 with little fuss. Using a VPN to my remote server. (even accessing Node-Red via WAN)
I am however encountering the majority of my headaches on the LAN side. I do not believe it is related to the PC, reason for saying this is that when I connect a cable directly between the PC and the PR1, I can access the full scope of the PR1 and Node-Red without interruption. In my office development environment same (working through switch), no problem which would indicate something small is missing in the traffic rules of the new router. Reading through your networking guides, I think I have ticked all the checkboxes.
I have included setup info on the PR1, Router Firewall port forwarding and traffic rules for you to have a gander. With this setup I can access and operate all functions except Node-Red (see image of point it hangs).
Port forwarding Rules:
I will send the rest in separate reply’s as the forum only allows me one embedded image
Regards
Robin