Hi Flika,
It took me a few times to read through your post to figure out what exactly you did, as it's not the recommended way to do things....however i think i spotted your issue - TL;DR, your persistence.conf file has a small typo:
Change :
echo "/union" > /mnt/UUI/persistence.conf
To:
echo "/ union" > /mnt/UUI/persistence.conf
(There should be a space between the "/" and "union" entries.)
The long version:
The persistence.conf file holds a list of paths which you want persistence to be enabled. The syntax of the file is:
<path> <type of persistence>
In our most common case, we want the whole root path (/) to persist any changes (union), which explains the syntax of the file. You can read more about persistence.conf here and here.
Keep us posted with your results!
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