Thanks again Sam - happy to report it works fine after the mod and with the code example given in the Ethernet Shield brochure from TinyCLR.
Also - I now understand why you did what you did - so proves I’m learning something.
Cheers,
Nick
^^^^ Glad to hear that everthing went well for you! 
Hooked up shield using Sam’s wiring trick. Works like a charm!
Thanks Sam!
For those who doesn’t want to cut the header and solder wires you can just use wire jumpers Like I did in the picture below.
^^^ Neat!
Hope you’re not going to use the UEXT extension on your Panda.
So you can still keep the Ethernet Shield’s header!!! :
Yes, I don’t have it soldered yet. But there are options: use it on the bottom of Panda, straight or right angled, etc. The final configuration depends on the project.