Macro Fails if Run As Action, Fine When Run Directly

I'm having a devil of a time figuring this one out. If I run the below macro on its own, it works as expected--disabling the checkbox control or ignoring it if the checkbox is already disabled. However, if I run the macro as a Macro Action inside a larger macro, the checkbox is apparently double-clicked--turned off then turned back on again! AND that happens if I highlight just the one action and Try it, so it isn't that a subsequent or prior action is altering the behavior.

Help?

The Sub macro is in an application-only group, while the macro calling it as an action is not app-specific, if that helps.

[SUB] Turn OFF Use Marker Names in Filenames.kmmacros (60 KB)