Add Docker to DEY-2.4 [ConnectCore 6UL SBC Express]

I want to enable Docker on my Digi CC6UL SBC Express. From what I can see, I need to add layer meta-virtualization, and it has a few pre-requisites (like meta-filesystems). So I downloaded the meta-virtualization layer (and checked out the rocko branch),

added this line to local.conf:
DISTRO_FEATURES_append = " virtualization"

and added these two lines in bblayers.conf:
/usr/local/dey-2.4/sources/meta-virtualization \

The build is successful, but when I try to flash the NAND it fails with:
[RECOVERY] Starting recovery…
Warning: Bad CRC, using default environment
MTD erase error on /dev/mtd1: Invalid argument
Error: can’t write fw_env to flash
Warning: Bad CRC, using default environment
MTD erase error on /dev/mtd1: Invalid argument
Error: can’t write fw_env to flash
[RECOVERY] [ERROR] No command found
[RECOVERY] The system will now reboot in 10 seconds
reboot: Restarting system

Entire log:

If I ONLY add this line
in the bblayers.conf then the flash is successful. If I then add the next line in bblayers.conf the flash fails.

Anyone knows how to troubleshoot or what might be wrong?

The way I flashed: After building I copied these 5 files and put them on the SD card:

Then i inserted the SD card into the CC6UL and pressed reset. After that I pressed a key on the keyboard to halt the boot and issued this command:
> run install_linux_fw_sd

Did you check your image sizes? are they smaller than the partitions they are going in to? There is not much free space available on cc6ul 256Mb variant unless you get rid of the recovery partition.

We realized that the image size would be a problem, so we purchased the Pro version with 1 GB of NAND. But that made no difference, the flashing still failed in the same place (immediately after starting recovery). If I remember correctly, the recovery partition is last in the list of partitions, and that should mean that it gets whatever is left of the NAND. That in turn should be more than enough considering that the boot and root partitions etc are roughly 500 MB.
So I think there is some other problem, I just can’t figure out what.

I am currently not working in that project so I don’t have access to the digi hardware. What I would like to test is to just include the virtualization layer. I have a feeling that it was at this precise moment that the CRC problem started to occur. The reason why I think that this is the case is that when I first tried to add Docker to the image I must have done something wrong, cause the image size ended up something like ~70 MB (and I got the CRC error).
When I managed to include Docker in the image, the size of root grew to roughly 140 MB.