Can't boot Ubuntu Mate 20.04 32 or 64 bit on RPI 4B with 2Gb RAM from card

I am getting the dreaded start4.elf is not compatible, get newer software. This hardware is listed as supported by UM, and I don't understand it. I am able to boot Ubuntu 20.04 Server and Raspberry PI O/S. It seems it is definately a memory issue.
This one is better slated for server level duties I guess, but I thought 2Gb was the minimum and thought I'd try it.


you need ubuntu in 32 B for the rpi 4 2G, 64B version will not work.
if you take the image planned for the pi 4 it should work (I have one that runs with it at home without any worries)