The backslashes do get the string to evaluate correctly (now the value of org-stuck-projects is indeed set to what you’d think it would be set to, where the first element is a string), but this does not yield the right output — C-c # still yields no output, and I do know there are projects I define as unfinished in the relevant file.

When I crop out the +FILE=… part of the string, I get the output I’m expecting, so I’m pretty sure my problem is with the syntax of the FILE selector.

Thanks!