- You’re setting the rule, and thus a string representing what will be run as the rule code once in place. As you already use quotes in the desired rule once, you need to use a different type (single vs double) of quote to enclose all the code
- You must use straight quotes for action code - your second expression uses curly quotes.
Thus, your stamp should be:
$Rule="$Subtitle=$ChildCount+' Notes';$SubtitleColor='bright green';"
Note, I reversed the nesting of single-outside-double quotes to double-outside-single. This is because the other way around, the Tinderbox parser is confused and only the first expression of the rule code gets set. Tested in v7.3.1