The first plate is just one material.

The second plate has a body (TPU) and core (PLA). This was my experiment to a) see if tow material would work/how to do it and b) see if this would impart more stiffness than an all TPU disc.

The stiffness was great! and it prints well and looks pretty cool. I would minimize material changes next time since it has to be manual with TPU. Also the core maybe needs to be thinner, stiffness was plenty good but I don't think there was enough non TPU outside of the core in some places.

For second plate, two material, you need to add this code to the filament start -
M400 U1

This manually pauses it at each filament change, so you can unload and then load the next filament and then continue on with the print.

Makerworld wouldn't let me upload it with the modified gcode.

Geesh, making it hard to share what I actually did - I also used an engineering plate, but had to switch it to something which would allow PLA?