Get Started with Adobe XD: Design issue (Mac)

I am new to XD and am working through the tutorials and am on Step 02: Import Content with Repeat Grid

Per the instruction in the lesson, I have tried to open the "chair images and text" folder which includes .txt and png files.

My issue is that I can't open the folder because all the files are grayed out (as shown in the attached screenshot).

How can I open this folder?

Thank you.