While trying to greatly simplify the sample camelcase rename example to make it more useful, I came across several strange behaviors. On an atrocious WIFI connection for the past couple of days but thought I'd try to report at least one:
The label for a custom checkbox doesn't seem to be used if the checkbox is set to false.
If you check the checkbox, the correct label appears, and it stays there if you uncheck it again. If the rename panel is closed and reopened, the correct label still shows.
Overall though, these custom options are a delight to work with. At some stage I'm sure someone will request a tooltip for these options and other such enhancements to that great feature.