Thanks for the advice.
I managed to get the old router working as a switch. (Disabled DCHP and disabled wireless)
The problem I'm now facing is that the wifi on the Plusnet hub doesn't have enough range.
I tried to set up the old router to be a range extender by enabling the wireless and setting the SSID and password to match those of my Plusnet hub. Admittedly, I don't really know what I am doing... but it seemed to work; I now had greater wifi range. However the wired connections to the old router no longer have internet access.
It seems that if I enable the wireless, it no longer acts as a switch.
Anybody have any ideas about what I need to do to make this work? I have looked online, but the terminologies all seem to differ to most of what see on my router setup screen.
