The error message I get is:
2022-02-06 13:04:32 +0000: The action “Run AppleScript” encountered an error: “The operation couldn’t be completed. (com.apple.Automator error -212.)”
When I browse the Quicktime entries in Script Editor, I don't see "Open Image Sequence" as an action. I'm ultra-new to scripting, so I don't know if this means it's been removed or that there is an option of "Open" I should be using.