I've added the script and created a new button with above lines:
@ifset:COLUMNSTOGGLE="scp:Newest File Column/NewestFileDate"
Set COLUMNSREMOVE="scp:Newest File Column/NewestFileDate"
Set COLUMNSREMOVE="scp:Newest File Column/NewestFileName"
@ifset:else
Set COLUMNSADD="scp:Newest File Column/NewestFileDate"
Set COLUMNSADD="scp:Newest File Column/NewestFileName"
When clicking this button I get those errors in script log:
The path was a network share, FWIW.
When using this button on a local drive C, for example, the columns are enabled (or disabled) but their content is empty.
Maybe I did not fully understand the intention behind those new columns?
Not sure what's going on there in both cases. I can't reproduce either of them, even with the ".." item turned on (which might have explained the null modified time, but doesn't seem to be a factor when I try it here).