LDDFM BETA crashes when clicking 'close'

I'm trying to add a 'close' button to my file manager, but when I click on it, it crashes with:

window:179: bad argument: string expected, got nil

Then it shuts down after a button press. What's weird is that there's nothing at the part of my program where it detects the click that would warrant that error (to my understanding), as that error is usually for entering an invalid argument for term.setBackgroundColor().

Here's the link for the paste. The line that detects the button press on 'close' is line 223. Please help!

run without multishell? see if you get a more helpful error?

I did that, and it gave me an error for line 149. That cleared it up. Thanks.

Thanks for the report, but we do not generally close threads in Ask a Pro.

Oh, okay. I reported this because the problem was very situational, and for a paste that people aren't expected to download from.