I have a heap of downloaded TCZs so would prefer to recover the situation that have to start again if possible
Here's a thought:
For recovery purposes recursively copy your entire tce dir to a vfat partition.
As vfat inherently lacks any capability of setting ownership and permission attributes, latter will just poof in the copy process.
This might possibly help distinguish issues, having to deal then only with /home and /opt, but leaving tce dir out of the equation.